Objective: to evaluate the patient safety culture in a primary care health unit. Methods: cross-sectional study conducted with 51 professionals linked to Primary Health Care. Data were collected using the self-administered instrument Medical Office Survey on Patient Safety Culture, translated, adapted and validated for use in Brazil. Descriptive statistical analysis was performed. Nurses, physicians, Community Health Agents, among other professionals participated. Results: the dimensions of the patient safety culture in Primary Health Care indicated opportunities for improvement or weaknesses in the service. The general assessment of patient safety and the global assessment of the quality of care provided in Primary Health Care were appointed as good or fair. Conclusion: the safety culture in Primary Care did not identify strong dimensions; there were problems with equipment, performance and availability of test results and exchange of information with imaging centers/laboratories in the care network.