OBJECTIVES: This study identifies the current status and problems of adverse event reporting system in Korean hospitals. The data obtained from this study will be used to raise international awareness and enable collaborative researches on patient safety. METHODS: We distributed the questionnaire developed by the Agency for Healthcare Research and Quality (AHRQ), USA to the 265 risk managers of hospitals by e-mail. Seventy-two percent of the risk managers responded to the inquiry. RESULTS: Eighty-five percent of the hospitals responded that they collect information regarding the event where harm has occurred or might have occurred to a patient. Seventy-five percent of the hospitals did not allow individuals to report occurrences without identifying themselves. Only 54% of the hospitals had an organized patient safety program that manages or coordinates all of the hospital's patient safety activities. The most frequent reason why errors were not reported was the fear of individuals being involved in the investigation and potential disadvantage resulting from it. Eighty-five percent of the hospitals produced reports of their adverse event data, but 68% of the hospitals did not distribute occurrence reports within the hospital. CONCLUSIONS: Lack of standardized reporting system, available information, procedures for protecting the reporting individuals, and mindlessness/indifference of the hospital employees are identified as the major problems. Therefore, it is crucial to address these problems to develop appropriate solutions, enable proactive involvement from the healthcare community, and change the overall patient safety culture, specifically protecting privacy, to increase the quality of service in the healthcare industry.