Background: Self-medication is a very common practice in many developing countries where mothers treat their children's illnesses without consulting a doctor. Aim: Assess knowledge, attitude, and practices of mothers of children under five years regarding self-prescribing medication in Beni-Suef City. Design: A descriptive research design was utilized. Setting: Maternal and child health care center (East Nile Medical Center) at Beni-Suef City. Sample: A convenient sample of 120 of mothers who had children under five years and accepted to participate in the study. Tool: A structured interview questionnaire, with four parts were utilized to collect data: the first part was to assess socio-demographic characteristics of mother, the second part was to assess mothers' knowledge about self-prescribing medication, the third part was to assess mothers' attitude toward self-prescribing medication and fourth part to assess mothers' practices towards self-prescribing medication. Results: the highest percentages of mothers were that their age 25: < 32yrs, highly educated, and married. 100% of the studied sample used self-prescribing medication although 50.8% of mothers needed 40 :< 60 min to reach the nearest primary health care and 44.2% of self-prescribed medications were antipyretic. 37.5% of mothers almost believed the disease was simple and easy to treat and always thought about the high cost of medical services. Mothers' knowledge regarding self-prescribing medication was 76% unsatisfactory knowledge, 57.5% of mothers had a negative attitude, 74% of mothers had moderate practice and 23% of them had positive practice regarding self-prescribing medication. Also, there was a highly statistically significant Correlation between total knowledge, total attitude, and total practices of mothers. Conclusion: Mothers' level of knowledge affects their attitude and practice toward Self-prescribing medication, Also knowledge level and attitude are influenced by the mother's educational status, occupation, and income but practice is affected by income only. Recommendations: Encouraging the implementation of health education programs for mothers regarding self-prescribing medication, with incorporating mass media to spread health education for a mass number of mothers.