Abstract: Basic Immunization coverage is still one of problems in Tulungagung district. For the last 3 years, the basic immunization coverage did not cover all the target infants. In 2018, from the target of 15,147 infants, there were 1,116 infants who did not receive immunization of Hepatitis B, 689 infants were not immunized with Bacillus Calmette Guérin (BCG) and 849 infants were not immunized for Oral Polio Vaccine (OPV 1). Aim of the study : To analyze the problems of basic immunization program. Method: This study is a descriptive observational study, conducted at Tulungagung District Health Office from January to February 2019. Identification of problems was done by conducting interviews, analyzing secondary data on basic immunization coverage of the Tulungagung health profile from 2016 to 2017 and section report Surveillance and Immunization in 2018. Prioritisation of Basic Immunization problems was done using Urgency, Seriousness, Growth (USG) criteria. Analysis of the problem cause was done by Fishbone methods.Results: Of the problems identified, the first priority problem in Tulungagung District 2018 is Hepatitis B immunization coverage does not reach the target. The root causes were poor immunization, under qualified workers in data collection and validation of targets, poor integration of Basic Immunization and Maternal and Child Health (MCH), lack of promotion and media campaign.Conclusion: Low Hepatitis B immunization coverage is a priority problem for basic immunization programs. Optimization of the integration of child and maternal health immunization program (MCH) is needed, periodic validation of program coverage and health promotion on immunization using creative promotional media.