Medication administration principles and errors for nurses caring for elderly patients play a significant role for improving elderly people health and decrease hospitalization. The current study aimedto assess medication administration principles and errors as perceived by nurses caring for elderly patients. Design: A descriptive research design was used in this study. Setting: The study was conducted at inpatient departments in Beni-Suef University hospital. Sample: A convenient sample of (120) nurses was recruited at the current study. Tools: Three tools were used I): Questionnaire sheet assessing respondents' opinions about Medication administration principles II): Observation checklist of Medication administration principles. III):  Opinionnaire sheet examined the types, stages, and causes of medication administration errors. Results: The majority of studied subjects (72.3%) applied the medication administration principles for caring for elderly patients. on the other hand, (27.7%) were not applying medication administration principles in general; the majority of the nurses (73.5%) observed doing the medication administration principles for caring for elderly patients. on the other side, (26.5%) observed not applying medication administration principles in general, most of the studied subjects (82.7%) agreed on all listed medication administration errors in the opinionnaire. Conclusion: Based on the results of the present study it was concluded that nurses demonstrated satisfactory competency levels regarding medication administration indicated by good practice demonstration level, medication administration principles, and medication errors. The current satisfactory nurses' scores of medication administration are the main reason for the increase in the importance of high-quality elderly patients' care. Recommended that: Developing educational programs and upgrading nurses with assessing patient's condition, documentation correctly in medication charts. Increase nurses' awareness regarding medication preparation to be administered (check labels, prepare injections, observed aseptic techniques).