Background: Performance appraisal helps in understanding the nurses work culture involvement and satisfaction, nurses' satisfaction with performance appraisal is a critical and important aspect for increasing intrinsic motivation and achieving better work outcomes among nurses. Aim: Evaluating the effect of training program about performance   appraisal system for head nurses on staff nurses' job satisfaction Research design: A quasi-experimental design was utilized in this study. Setting: The study was conducted at Benha Fever and Naser General Hospitals. Subjects: consisted of all head nurses (71) and sample random sample (261) staff nurses. Tools: Three tools were used; I. Performance appraisal knowledge questionnaire, II. Performance appraisal observational checklist and III. Staff nurses' job satisfaction questionnaire. Results: More than one third of the head nurses had satisfactory knowledge at the preprogram phase and improved to be majority (83.1%& 78.9%) at the post program & follow up program phase respectively. More than two fifth of head nurses had adequate practice of performance appraisal system at the preprogram phase and improved to be majority (83.15% & 85.9%) at post program & follow up program phase respectively.  In addition, nearly one fifth of staff nurses had job satisfaction at the preprogram phase and increase to more than half (55.9% & 52.1 %) at the post program & follow up program phase respectively. Conclusion: There was statistically significant positive correlation between the head nurse's knowledge, practice regarding performance appraisal system and staff nurses' job satisfaction. Recommendations: Allow nurses to see their ratings and appraisal results to identify the weakness and strength point of performance. Assess the effect of application of performance appraisal on patient safety.