Hypertension is one of the main risk factors for cardiovascular diseases. Nursing carries a large responsibility in care delivery to hypertensive individuals. Thus, the goal was to assess a nursing team's knowledge on hypertension and its treatment before and after educational interventions. A questionnaire was used, addressing theoretical aspects of hypertension knowledge among nurses (5), technicians (2), auxiliaries (11) and community agents (37) at two Basic Health Units in São Paulo City, Brazil. For statistical analysis, Student's T test was used, as well as variance analysis and p < 0.05. A knowledge increase was verified after the educational interventions for the group constituted by nurses, technicians and nursing auxiliaries (84.6 +/- 12.0% vs. 92.7 +/- 15.0%, p < 0.05), while no significant change occurred for community health agents (80.8 +/- 12.2% vs. 83.5 +/- 24.0%). Thus, it was concluded that the educational actions were effective and must be put in practice in the nursing team, which they can influence the improvement of care delivery for hypertensive patients.