Background: Nowadays hematopoietic stem cell transplantation (HSCT) is a reputable treatment modality for many hematological disorders with decisive indications. Aim: This study aim to appraise the effect of Social mediaassisted in-services training program for nurses regarding hematopoietic stem cell transplantation in 57357 outpatient clinic. Research design: A quasi-experimental design was used in this study. Setting: The study was conducted at 57357 out-patient clinic affiliated to Cairo city, Egypt. Subject: a convenient sample that included (50) nurses. Tools: a structured interview Questionnaire tool that cover four parts. Part I: demographic characteristic, part II: nurses knowledge part III: attitude, part IV: reported practices (pre and post). Results: This study displayed statistically significant enhancement in nurse's knowledge, attitude, and reported practices (14.58 ± 1.85 to 23.92 ± 2.31) (20.32 ± 2.78 to 36.84 ± 3.32) (48.94 ± 5.05 to 65.50 ± 2.73) respectively pre VS post program. Conclusion: The current studies demonstrate importance of social media assisted in-services training program for nurses to improve their knowledge, attitude, and reported practices. Recommendation: Continuity of in-services training program for nurses in different health care setting