Background Medication errors are frequently identified in healthcare institutions and pose a risk to patients. The mass gathering during Hajj may expose the pilgrims to numerous health risks. No study has reported the extent of medication errors during Hajj in Saudi Arabia.Weinvestigated the rate, nature, reporting, severity, and causes of medication errors in Hajj pilgrims. Methodology A retrospective analysis of medication errors reported by healthcare professionals was conducted from July 5, 2022, to July 15, 2022, at Mina Al Wadi Hospital, Saudi Arabia. This study included all medication error report forms collected during the Hajj season. The National Coordinating Council for Medication Error Reporting and Prevention Index was used to classify the severity of medication errors. Results There were reports of 43 medication errors in 3,210 prescriptions. The medication error incidence rate was 1.5% (43/3,210). The highest proportion of medication errors (83.72%, 95% confidence interval (CI) = 72.69-94.75) occurred during the prescribing phase, and 97% (95% CI = 93.16-100.0) of medication errors were classified as near misses. Wrong drugs (23.25%) and frequency (18.60%) were responsible for nearly half of the medication errors. Lack of drug information was the leading cause of reported medication errors (58.14%), followed by environmental, personnel, and workload issues (23.25%), and look-alike/sound-alike medication issues (18.60%). Conclusions This study found that the incidence of medication errors was consistent with the global standard, and many of them did not reach pilgrims and were preventable. This highlights the importance of targeted interventions. Incorrect medication was the common type of medication error, highlighting a crucial area for intervention and improvement. Lack of drug information was the primary underlying factor in the occurrence of medication errors. Pharmacists were more likely than other healthcare professionals to report medication errors, highlighting the importance of their involvement in improving medication safety among pilgrims. Future research needs to focus on examining the effectiveness of interventions (e.g., provision of education regarding medicines and medication review) in reducing medicine-related events during Hajj.