Background: Patients' safety is the main concern of all health-care systems around the world; one of international patient safety goal is medication administration safety aim: determine the effect of patient safety training program for nurses on medication administration at Damanhour Chest Hospital. Used for applying this study subjects and method: Design: Quasi-experimental design. Setting: study was carried out  at critical care unit in Damanhour Chest Hospital. Subjects: Sample of the study staff nurses working at above mention setting with total number 64 nurses. Tools:   Six tools were used, Tool I:  Nurses' knowledge regarding patient safety. Tool II: Nurses' knowledge regarding medication administration questionnaire. Tool III: Observational chick list for Nurses' skills regarding patient safety. Tool IV: Observational chick list for Nurses' skills regarding medication administration. Tool V: Nurses' attitude regarding patient safety questionnaire. Tool VI: Nurses' attitude regarding medication administration questionnaire. Results:  Revealed that there were high statistically significant difference of total nurses' knowledge, skills and attitude regarding (patient safety and medication administration) during all phases of the program with P- value = 0.000 at post program and follow up compared with preprogram. Conclusion: patient safety program for nurses on medication administration had a positive effect on nurses' knowledge and skills regarding patient safety and nurses' knowledge, skills and attitude regarding medication administration. Recommendations: Develop procedures manual include procedures and techniques used in nursing care specially medication administration procedures.