Context:Medication errors are the most common types of medical errors in hospitals and leading cause of morbidity and mortality among patients.Aims:The aim of the present study was to assess the knowledge of healthcare professionals about medication errors in hospitals.Settings and Design:A self-administered questionnaire was distributed to randomly selected healthcare professionals in eight hospitals in Madinah, Saudi Arabia.Subjects and Methods:An 18-item survey was designed and comprised questions on demographic data, knowledge of medication errors, availability of reporting systems in hospitals, attitudes toward error reporting, causes of medication errors.Statistical Analysis Used:Data were analyzed with Statistical Package for the Social Sciences software Version 17.Results:A total of 323 of healthcare professionals completed the questionnaire with 64.6% response rate of 138 (42.72%) physicians, 34 (10.53%) pharmacists, and 151 (46.75%) nurses. A majority of the participants had a good knowledge about medication errors concept and their dangers on patients. Only 68.7% of them were aware of reporting systems in hospitals. Healthcare professionals revealed that there was no clear mechanism available for reporting of errors in most hospitals. Prescribing (46.5%) and administration (29%) errors were the main causes of errors. The most frequently encountered medication errors were anti-hypertensives, antidiabetics, antibiotics, digoxin, and insulin.Conclusions:This study revealed differences in the awareness among healthcare professionals toward medication errors in hospitals. The poor knowledge about medication errors emphasized the urgent necessity to adopt appropriate measures to raise awareness about medication errors in Saudi hospitals.