Introduction Young population accounts 1.8 billion which is 24.3% of the global population and 1.4 billion young were in developing countries. Youth is Period of transition and experimentation, involves distinct physiological, psychological, cognitive, social & economic changes. They involved in risky sexual behavior such as unprotected sex, substance abuse & dangerous recreational activities, can be caused by, Curiosity Peer pressure and Sexual maturation. However on the presence of such reality reproductive health issue of adolescents & youth were neglected by community and health care providers . Accessing RH service for youth is standardizing the quality of services with the characteristics of accessible, acceptable, comprehensive, appropriate, equitable, effective and efficient and an approach which brings together the qualities that young people demand, with the high standards that have to be achieved in the best public services. However the culture of youth to access RH service was limited as result they are prone for different problems, such as teenage pregnancy, unsafe abortion and sexually transmitted infections (STI) . According to world health organization Up to 60% of new infections occur among 15-24 yrs in developing countries and the vast majority of adolescents in low income country face unplanned pregnancy [3&4]. Youth are single largest group in the country, accounts for 42 % of the total population. In recognition of such realities the national youth and educational policies focused on how to reach young people in Ethiopia with relevant services. Yet, characteristically there is wide range of variation in terms of age, sex, schooling, residence and needs posing opportunities and challenges to programs designed for young people .Majority of youth lack information and they are low trend of utilizing reproductive health service due to, fear of being judged by service provider, lack of privacy, feeling that services are intended for married people and unaware of service locations or services offered [6&7]. Ethiopia government has developed a 10-year National Adolescent and Youth Reproductive Health Strategy. However, they have focused on the clinical aspects but the non-clinical aspects are poorly addressed so, ensuring effective interventions during this period protect public health investments. As a result, utilization of reproductive health service has become a primary concern of Sexual and Reproductive Health rights in the country [8&9].Studies show that adolescents and youth in Ethiopia are prone to various forms of RH problems including: early marriage, unplanned pregnancies, and sexually transmitted infections including HIV. Factors associated with utilization of reproductive health service were, lack of information, providers approach, facility readiness and financial dependency [10&11].Current studies focused on higher learning institute students revealed that one third of university students have had sexual experience. Of these, nearly two third were found to have sexual experience already before joining the university which evidences that RH problems manifest early on and calls for interventions at early stage .Hence, evidence on utilization of reproductive health service is very limited in Ethiopia. Therefore, this study aimed to asses’reproductive health service utilization and associated factors among youths in Dilla town, Southern Ethiopia, 2017.Main textMethods Study design, study population and sampling procedureA community based cross-section study design was carried out from June 1-30/2017 among youth in Dilla town, Gedeo zone, southern Ethiopia. Dilla town is located 394 km from South of Addis Ababa which is the capital city of Ethiopia. According to 2007 census the population of the town was estimated to be 101,304 and 43, 463 were youth population . Hospital found in the city is: one governmental teaching hospital. The city had two health centers and one maristope clinic. The study units were youths living in selected kebele for at least six months were included for the study.Sample size was determined byusing single population proportion formula with the following assumption: 95% level of confidence (Z=±1.96), Margin of error (d=5%), none response rate=10%, Prevalence=50%, considering design effect 2and sample size for quantitative analysis was 845.A multistage sampling procedure was used to select e study participants from youths aged 15–24 years and living in the town. The town was stratified into eight strata, using the existing division of the district. From each district, one kebele was selected by a lottery method. The study samples were proportionally allocated to the youths’ population size of each kebele. In order to develop a sampling frame, a baseline enumeration of the total households in each kebele was conducted. Then, a simple random sampling technique was used to select the eligible households from the sampling frame. Data collection methodsThe data was collected face to face using structured and pretested questionnaire interviews. The questionnaire was prepared by reviewing existing literatures [14, 15] which consist of socio-demographic characteristics, knowledge about and attitude towards RH service, and level of utilization and the factors associated with RH service. Three (03) nurses who have YFS training were recruited and training was given for 02 days on the objective, relevance of the study, confidentiality of information, respondent rights, informed consent, and technique of interview; 02 health professional who have 1st degree (BSC midwife) were trained and supervise the data collection. The qualitative data was collected using semi-structured interview guides designed for RH service providers and the youth themselves. FGDs and in-depth interview carried in Amharic until the point of saturation was reached. The discussions were tape recorded with permission from the participants. The transcribed data were compared with the notes taken during discussion. Data analysis Data entry was done using EPI Info 3.5.1 and exported to SPSS version 20.0 software for analysis. The presence of association between independent and dependent variables was determined using odds ratio with 95% confidence interval by applying logistic regression model. The qualitative data were transcribed and typed in word, and translated back into English by the investigators and analyzed using thematic analysis. The main thematic areas from the qualitative data were identified, coded, and significant quotes were also noted in the text.ResultSocio-demographic characteristic of respondentA total of 845 youth were involved in this study and provided a response rate of 100%. The age of participants ranged from 15-24. The mean age (in years) of the studypopulation was 17.02 ± 5.45 years.Gedeo was a dominant ethnic group, which accounted 36.9% (n = 312) See table1. Knowledge and attitude towards reproductive health servicesMajority 768 (90.8%) were understood that reproductive health service is important and most of the youth had information about reproductive health service from peer educators 204 (24.1), youth club 188 (22.2%) and school min-media 213(25.2%)see fig1.Abortion (31.3 %), unintended pregnancy (28.7 %), unsafe sexual practice (17.6%), and STIs/HIV/AIDS (22.4%) were the major RH problems described by youths.The reproductive health service known by youths were family planning (36.7%), abortion care (26.4%) and STIs including HIV/AIDS (31.4 %) and health education (5.5%). Majority of the respondent had positive attitude. Response from the youths that using condom (32.4%) abstaining from sex (40.1% %) followed by faithfulness to partner (27.5 %) were the major modes of preventing HIV/AIDS reported by the youth.Utilization of reproductive health servicesThe prevalence of reproductive health service utilization in Dilla town was 34%. During focu group discution youth described reasons why they visit reproductive health service and they described for support of family member for health care service, for other medical service.43.7 % of youth were visits reproductive health service for the first time and (4.6% %) got counseling service, (14.3 %) were for contraceptive services, (3.8 %) were for pregnancy related servicesand post abortion careaccounts (1.1 %.). Factors associated with utilization of reproductive health servicesPeer educator [AOR = 3.12, 95 % CI (5.76, 8.3)], school min-media [AOR = 1.79, 95 % CI (1.00, 3.19)], youth club [AOR = 2.78,95 % CI (3.67, 9.11)] and approach of health care provider [AOR = 4.11, 95 % CI (5.54, 11.23)] as source of information were factors associated with reproductive health serviceutilization Table 2.During the time of discussion, Facility readiness was repeatedly raised as a factor that prevented the youth from acquiring essential RH services. A 19- year male discussant said “while you seek reproductive health service and moved to health facilities, the service were not provided in separate room and we lost our confident and privacy so that we become ashamed of discussing our problem.”A 17 year- old female discussant who visited the facility for abortion service described “while at the time of my visit the provider asked me how can I get pregnant and I told him that from my boyfriend and providers told me it is sin so that I ashamed and lost confident trough out the process.” other Moreover, an 18 years old male discussant indicated about setup of the facility “when he visits the health facilities the environment was not conducive so he was afraid of sawing community member and left the facilities before getting the service.”At the time of, in-depth interview they were asked about provision of the service, the respondent from public institutions explained that there is no specifically designed RH services room for the youth in their institutions as well RH services are offered for youths without giving them aspartate room so that they are treating them as adult clients. Additionally, the respondents of the in-depth interview were asked whether they have been given training on RH and approaching the youths. The respondents reported that they have taken such trainings and are confident that they could respond to the needs of the youth. Provider from the government institution said, “…. I have obtained trainingon how to provide the service, But I am assigned in another unit and am working in RH clinic as aback up so that which is not appropriate for me providing the service per standard.”Discussion Reproductive health is a major public problem in developing country and this problem increase its magnitude which brings a major public impact.The aim of this study was assessing reproductive health service utilization and associated factors among youths in Dilla town, Gedeo zone SNNP 2017.The prevalence reproductive service utilization in Dilla town was 34%.This result was inconsistence with study conducted in Bahir Dare 32.2% , in Addis Ababa 29%  and in metekel 21.5% , and lower than study conducted in Harar town, east Ethiopia, and west harergea Ethiopia which is 63.8% and 42.1% respectively [19&20]. This difference might be due to different in study setting and time.This study revealed that (4.6% %) got counseling service, (14.3 %) were for contraceptive services. This is lower than study done in dibrbrehan town Counseling and testing service for HIV service accounts 175 (43.6%) followed by, modern contraceptive users 88 (21.9%), and STI diagnosis and treatment service users 43 (10.7%) .Current study described most youth’s visits RH services were for library and recreational services (37.2%). This is in line with study done on Addis Ababa . This study revealed (4.6%) of youths received counseling services,this finding was lower than study conducted in Harar town, nearly 60 % of the study participants received reproductive counseling, , similarly lower than study conducted in Kenya (38.7 %%). This difference might be due to poor trends of RH services and due to approach of providers which is not friendly.ConclusionThe prevalence of reproductive health services was low in Dilla town Gedeo Zone. Sources of information for RH services were influence on its utilization among the youths. The utilization of RH services was higher among the youths who received information from health care providers, friends and schools, in this study. More emphasis should be made by all relevant stakes to create to strengthening of the awareness creation strategies among the youth to increase the utilization of the services.Limitation This study was a subjective bias due to most outcome variable was measured by subjective report and Causality can’t be confirmed because the research design is cross sectional.