The dangerous events caused by medication errors are one of the main challenges faced in the hospital. The current study aimed to evaluate the effect of in-service training program on minimizing nursing intravenous medication process errors by syringe through intravenous catheter. Design; Quasi-experimental study was used in this study. Setting: Surgical wards (A, B, and C) at Assuit University Hospital. Subjects: all available nurses were in the age group between 18-60 years, and both male and female. Tools: Nurses knowledge questionnaire sheet, Nurses' practice checklist for intravenous medication process, and in-service training program. Results: the majority of nurses were females, two thirds their age ranged from (20 >30 years), and their years of work experience were more than 10 years. The majority of them had not attainting training program related to intravenous medication process. Conclusion: there was statistically significant difference between pre and post implementation of in-service training program as regard total scores of knowledge and practice about nursing intravenous medication process errors. Recommendations: Development of standard guideline medication administration process should be available at all units in the hospitals.