Background: Ambulatory care is provided in a variety of settings, including physician's offices, hospital-based clinics, and public health clinics. The Aim of this study was to evaluate the effect of training program for improving the nurse's performance toward infection control in ambulatory care units. Setting: This study was conducted in ambulatory care units at University Ain Shams specialized hospital, Cairo Governorate, Sampling: A purposive sample of 83 nurses working in ambulatory care units in Ain Shams specialized hospital, Study design: descriptive Study. Tools: two tools were used for data collection, First: An interviewing questionnaire divided into two parts: Part 1 nurses Socio-Demographic, Part 2 Nurses knowledge. Second: Observation checklist for assessing nursing performance regarding infection control Results Reveals that 53.8% had correct performance toward infection control preprogram, improved to 87.4% post program implementation, there were statistically significant differences between nurse's total knowledge scales and subscales in Pre and Post program. Also reveals that there were highly statistically significant differences related to nurses correct performance score level pre and post program. Conclusion: education training program reported remarkable improvement in ambulatory care nurses' knowledge and performance toward infection control. Recommendations the study recommended that Continuing training courses for nurses to demonstrate nurses' compliance/ performance/ utilization of standard precautions of infection control by the infection control team.