Objective To calculate unmet need for contraception according to revised definition,mapping the contraception service needs and analyze factors related to the unmet need for contraception in Nusa Tenggara Barat(NTB).Methods This research design was cross sectional, using data from Indonesia Demographic and Health Survey 2012. Subjects were from 1 362 household, and were married women aged 15-49 years in NTB Province(685 women). Calculating method of unmet need for contraception used revised version, and analysis method was univariate, bivariate, and multivariate(Logistic regression).Results Majority of married women aged 15-49 years in NTB need contraception service(73.1%). However, it was known that met need for contraception was only56.0%. Meanwhile, unmet need rate for contraception in NTB was 17.1%, specifically11.5% for spacing and 5.6% for limiting. Factors contributing to unmet need for contraception in NTB were: household assets at above average(OR=0.77), parity of2-3 children(OR=0.73), women with junior high school education level(OR=0.68),never be visited by health workers(OR=0.68).Conclusions Factors that contribute to unmet need for contraception in NTB are household assets, parity, education level, and visited by health workers. Government has to prioritize those four factors in policy intervention and promotion of family planning participation program in NTB. Objective To calculate unmet need for contraception according to revised definitions, mapping the contraception service needs and analyze factors related to the unmet need for contraception in Nusa Tenggara Barat (NTB). Methods This research design was cross sectional, using data from Indonesia Demographic and Health Calculating method of unmet need for contraception used revised version, and analysis method was univariate, bivariate, and multivariate (Logistic However, it was known that met met for contraception was only 56.0%. Meanwhile, unmet need rate for contraception in NTB was 17.1 %, specifically11.5% for spacing and 5.6% for limiting. Factors in to unmet need for contraception in NTB were: household assets at above average (OR = 0.77), parity of2-3 children OR = 0.73), women with junior high school education level (OR = 0.68), never be visited by health workers (OR = 0.68) .Conclusions Factors that contribute to unmet need for contraception in NTB are household assets, parity, education level, and visited by health workers. Government has to prioritize those four factors in policy intervention and promotion of family planning participation program program in NTB.