Background: Bariatric surgery refers to weight reduction surgeries for obese persons mainly by restricting their food consuming through a variety of surgical procedures performed on gastrointestinal tract by reducing the size of the stomach. Aim of the study: Was to evaluate the effect of an educational program on minimizing complications for patients post bariatric surgeries. Design: Quasi-experimental design was utilized to fulfill the aim of the present study. Setting: Surgical departments and outpatient clinics at Benha University Hospital. Subjects: A purposive sample of 45 bariatric patients based on specific inclusion & exclusion criteria. Tools: Two tools were used in the study. Tool I: Patients' structured interview questionnaire. Tool II: Postoperative complications assessment and follow up sheet. Results: Only more than one fifth of the studied patients had good level of knowledge at preprogram implementation compared to less than half, two thirds & majority of studied patients respectively during 1st month, after 3 & 6 months post program implementation. There was a significant statistical difference between 3 months and 6 months post program implementation in relation to all items of late complication among the studied patients. There was a significant statistical relation between total knowledge score and studied patients residence, educational level as well as occupation preprogram implementation and after 3 months post program implementation at P-value < 0.05. Conclusion: Implementing of an educational program had statistically significant improvement of knowledge and reduction in the incidence of complications among bariatric patients. Recommendations: Replication of the study using a larger probability sample from different geographical regions for generalization of results.