Background: Maternal infections around delivery are one of the main factors contributing to maternal mortality worldwide, competency outcomes and performance assessment model is an outcomes-based approach to designing, implementing infection control measures at delivery room. Aim of the study was to evaluate the effect of implementing competency outcomes and performance assessment model on maternity nurses 'performance regarding infection control measures at delivery room. Design: A quasi- experimental study design was utilized. Setting: The study was conducted at the delivery room in Benha university hospital. Sample: A convenient samples of 70 maternity nurses at delivery room. Tools: Four tools were distributed: A structured interviewing questionnaire, an observational checklist for nurse's performance regarding infection control measures at delivery room, nurse competency scale and nurse's satisfaction questionnaire. Results: there was a highly statistically significant difference among total mean scores of all domains of studied nurses' knowledge and total mean scores of all practices of studied nurses' performance regarding infection control measures as well as nurses' competency scores in implementing infection control measures at delivery room pre and post model implementation. Most of studied nurses were satisfied after implementing competency outcomes and performance assessment model. Conclusion: there were a highly statistical significant improvements in nurses' total knowledge, total mean scores of all practices of studied nurses' performance regarding infection control measures, competence score and satisfaction level post competency outcomes and performance assessment model compared to pre. Recommendations: distribute the present study results of competence assessment and performance model as an updated data for improving the hospital infection control measures.