ABSTRACT Objectives: to analyze structural and process conditions in National Immunization Program Information System establishment. Methods: a cross-sectional study conducted in 307 vaccination rooms in the state of Minas Gerais in 2017. For data collection, a multidimensional questionnaire was used. Descriptive data analysis was performed. Results: vaccination rooms have basic inputs necessary for System establishment. The greatest problems relate to professional practice. Low enrollment of population, failures in the active search for absentees, vaccine scheduling and absence of reports to monitor vaccination coverage were identified. Training was considered insufficient and ineffective. Conclusions: Immunization Information System is an essential technological innovation for the management of immunization actions. However, the production of timely records and the use of information are still challenges. Investments in training are required to ensure System’s management and operationalization activities.