Objective: To determine knowledge, activities and barriers in primary health care nurses in the basic standards in Barranquilla. Methods: Cross-sectional study. Participants were 79 key representative subjects working in the first level in public and private health institutions in Barranquilla. Instruments: ad hoc Survey. Data were analyzed using SPSS version 21 in Spanish. A bivariate analysis accompanied by proof of significance (chi square) was performed. Participants signed informed consent. Results: 64.6% displayed insufficient knowledge regarding PHC (4.8 / 8.0 possible points), noting that only 2.6% achieved a better score (6/8 points). As one progresses through work experience (over 3 years), knowledge (p = 0.05) increases. No differences in knowledge according to the performance area, level of education and age were observed. The median and modal frequency of barriers identified was 9/14; The role of policies and administrative aspects related to implementation, management and evaluation of primary health care is unknown for the latter. Weaknesses were observed in advocacy, prevention, surveillance and environmental monitoring. Conclusions: The level of knowledge displayed demonstrates the need for training, mobilization and empowerment with regard to primary health care for the nurse. Ignorance of aspects inherent to policy, planning and management in PHC hinders its implementation in the territory, which hinders the positioning and role of nursing in primary care.