Introduction: High blood pressure is a chronic disease requiring long-term treatment,which despite being asymptomatic, leads to fatal complaints and complications. Therefore, the present study was aimed to determine the effect of the education based on Self-efficacy theory on Self-care behaviors of hypertensive Self-help groups in integrated health service centers in Mashhad in2019. Methods: This was a quasi-experimental study in which 80 female patients with hypertension were randomly divided into the test and control groups. The educational intervention was based on the theory of Self-efficacy for the test group. Data collection tools were a three-part questionnaire including: demographic information and a standard questionnaire of Self-efficacy and hypertension Self-help. Data were analyzed using independent t-test, Mann-Whitney, Chi-square, Fisher's exact test, Friedman test and repeated measures, and analysis of covariance by SPSS software version 20 with a significance level of 0. 05 Results: There was a significant difference in Self-efficacy (P <0. 001) and Self-help (P <0. 001) scores and controlled blood pressure between the test and control groups. The Self-help score was increased by 0. 84, which was also statistically significant (p <0. 001) Conclusion: Intervention based on the theory of Self-efficacy can be effective in developing Self-help and Self-efficacy in hypertensive Self-help groups. Therefore, it is suggested that this theory be used in educational planning for patients and hypertensive Self-help groups.