To investigate the status of medical accident attack rate and medicare utilization during last 27months from 1st Oct., 1977 to 31st Dec. 1979 in the area under Sam Wha Medicare Insurance Union, the study was carried out through analyzing the medicare records of patients who were enrolled. "The medical accident" in this study was used as the meaning of the state that the people who have been treated morbid condition with insurance money. For the study, 2 doctors and one nurse were mobilized and the results are as follows: 1) The total number of the Medicare Insurance Union members among the 37,044 total population of the study area, (Hea-mi, Unsan, Eumam Myun) were 57, 35 composed of 3,000 males (52.3%) and 27, 35 females (47.7%) in 1977, 3,383 composed of 2,006 males (59.3%) 1,377 females (40.7%) in 1978, 2,573 composed of 1,437 males and 1,336 females (44.2%) in 1979. 2) Total number of medical accident attack cases were 6,774 case (partially overlapped the number of the 1977 with that of the 1978) and average annual medical accident attack rate per 1,000 population was 700.9. 3) Five major disease group in the past three years were disease of the respiratory system (177.7), disease of the digestive system (165.8), disease of the skin and subcutaneous(64.9), symptoms, signs and ill-defined conditions (64.6), any injury and poisoning (51.9). Mental disorders (32.6) was the 6th order disease group. 4) The order of the medical accident attack rate of age group per 1,000 population per year was the year group of 0~4(877.8), 45~64(832.6), 25~44(810.3), 5~14(495.1) 15~24(494.7) 65 and over (460.7). 5) Medical accident attack rate of age group per 1,000 population in the 5 major disease groups were the year group of 45~64 (100.0) in the mental disorders 0~4(525.1) in the disease of the respiratory system 45~64 (328.5) in the disease of the digestive system 0~4 (202.8) in the disease of the skin and subcutanous tissue, 25~44 (98.3) in the accidents and poisoning. 6) Monthly medical accidents attack rate were 87.0 in the winter (Dsc., Jan., Feb.) and 86.2 in the summer (Jun., July, Aug.). So the trend of the medical accidents attack rate during the year was bimount figure. 7) Monthly medical accidents attack rate in the major disease group were highest in Jan., Apr., (31.1) in the disease of the respiratory system, in Jan., Feb., Mar. (24.9) in the disease of the digestive system, in Jan., Jun., Aug. (9.8) in the injury and poisoning. 8) Duration of the treatment of the 93.1% of the total cases were within 5 days. 9) 299 cases (4.5%) of the total number of cases, 6,587 cases were referred to secondary and tertiary medicare facilities. 10) The order of the major 10 kinds of diagnosis of the disease, 6,587 cases during 27 months, were URI and chillness (1,063 cases, 16.1%), gastritis(830 cases, 12. 6%) dermatitis(360 cases, 5.5%), bronchitis(291 cases, 4.4%), neurosis (284 cases, 4.3%), contusion (165 cases, 2.5%), tooth extraction (157 cases, 2.4%), tonsillitis (109 cases, 0.7%), laceration (107 cases, 1.6%), neuralgia (105 cases, 1.6%), arthritis (104 cases, 1.6%), otitis media and mastoiditis (103 cases, 1.6%), so total case were 3,678 cases (55.9%).