BACKGROUND: All population had been taken the medical insurance period. Because the most patients like the third medical institute, the many problems of the side effects in the admission, bed lacks, etc were occurred. The aim of the study was analysed several factors to decrease the etiology of the cancellation in the elective and emergency surgery occurred in the admitted patients for operation. METHODS: We examined the etiology and cancellation in the elective and emergency surgical patients from July 1st to December 31th, 1997. Total number, department, anesthetic type, etiology and cancellation of the elective and emergency surgical patients were recorded daily. Total number, the important etiologies and department of the cancelled cases were also recorded daily. RESULTS: The total and cancel number of the operative patients were 5,415 and 578 cases. The cancel rate of the total operative, elective and emergency surgical patients was 10.7%, 10.7% and 10.6%. In general anesthesia, the cancel rate of the total operative, elective and emergency surgical patients was 10.6%, 10.4% and 11.1%. In regional anesthesia, the cancel rate of the total operative, elective and emergency surgical patients was 11.9%, 14.9% and 4.9%. By monthly, the peak and the lowest cancel rate of the total operative patients was August as 18.5% and October as 4.8%. The single most frequent etiology was affairs of operator or operating department. The second was no admission. The peak cancal rate of department was pediatric surgery. CONCLUSIONS: We found that there were several factors to decrease the etiology of the cancellation in the elective and emergency surgery performed in the operation room. These were a careful preopertive evaluation of patient's physical status and results of the laboratory examination before hospitalization, removal of affairs of the operator and operating department, removal of no admission, appropriate schedule of elective surgery, consultation with anesthesiologist, prevention of the inappropriate operative schedule, etc.