Based on the statistical data of FKMIS during five years from 1981 to 1985, the major findings of studying on the treatments of employee's medical insurance covered people were made as follows. 1. During five years, the total number of treatment case was increased 25.14% annually, and so doubled. The consultation rate was increased from 2.086 to 2.856, showng annual increase of 8.17% and total increase of 36.91%. In the case of in-patient, the rate was from 0.056 to 0.602, showing annual increase of 2.58%. And in out-patient, the rate was from 2.030 to 2.794, showing annual increase of 8.31%. The male: female ratio of treatment case was changed from 1: 1.1 to 1:1.2. 2. Case of chronic disease was on the increase every year. The ratio of medical expenditure of that disease to the total medical expenditure was increased from 22.99% in 1984 to 25.0% in 1985. 3. As a whole, the consultation rate of circulatory disease was increased from 26.10 in 1981 to 46.53 in 1985, showing an nual increase of 15. 55 %. The rate of in-patient was increased from 2. 06 to 2.94, showing annual increase of 9.30%. The rate of out-patient was from, 24.04 to 43.59, showing annual increase of 16.04%. 4. The duration (days) of circulatory, disease in 1985 by types is as follows. In the case of in-patient, rheumatic fever rehumatic heart disease (22. 67), ischaemic disease (17.39), ccrebrovascular disease (17.18), disease of pulmonary circulation and other from of heart disease (15.82), hyperte nsive disease (13.18), other disease of circulatory disease(11. 55). In the case of out-patient, visiting day (11.57 day) and medical expenditure per case (7,853 won) is lower than that of other diseases (4.39 day, 4,361 won). 5. Cases of circulatory chronic disease were two times as many as those of non-chronic disease. Incidence of the out-patient was shown higher than that of in-patient. In the case of duration per case, the chronic disease (12.92 days) was longer that of non-chronic disease (9.8 day). 6. The male: female ratio of chronic rheumatic heart disease is 34.56 : 65.44 (in-patient) and 34. 67 : 65.33 (out-patient). The consultation rate(case per 1,000 persons) was increased from 1.11 in 1983 to 1.30 in 1985, showing annual increase of 8.22 %. The duration, visiting day, was decreased slightly, but medication day wasincreased from 13. 93 in 1983 to 16.72 in 1985, showing annual inc rease of 9.56%. 7. The male: female ratio of hypertensive dise ase (case) was 39.36 : 60.64(in-patient) and 40.67 : 59.33 (out-patient). The consultation rate was increased from 19.59 in 1983 to 25.36 in 1985, showing annual increase of 13.78%. Duration, visting day, was decreased slightly, but medication day was increased from 11.82 in 1983 to 12.77 in 1985, showing annual increase of 3.94%. 8. The male:female ratio of chronic pulmonary-ischaemic heart disease (case) was 48.90 : 51.10 (in-patient) and 43.66 : 56. 34 (out-patient). The consultation rate of chronic pulmonary-ischaemic heart disease was increase from 0.69 in 1983 to 1. 12 in 1985, showing annual increase of 27.40%. Duration, visiting day, was decreased from 2.67 in 1983 to 2.36 in 1985, and medication day was decreased from 0.69 in 1983 to 1.12 in 1985, showing annual decrease of 2.09%, 9. The male: female ratio of cerebrovascular disease (case) was 47.90 : 52.10 (in-patient) and 52.28:47.72 (out-patient). The consulatation rate was increased .frorm 2.12 in 1983 to 2.89 in 1985, showing annual increase of 16.76%. Duration, visiting day, was decreased slightly, but medication day was increased from 12. 67 in 1983 to 13.85 in 1985, showing annual increase of 4.55%. 10. In case of artery and capillary disease, the male: female ratio of case was 61.80: 38..20 (in-patient) and 51.77 : 48. 23 (out-patient). But duration, visiting day, was increased from 3.45 in 1983 to 3.60 in 1985, showing annual increase of 2.15 % and the medication day was increased from 10. 06 to 10.18, showing annual increase of 0.59%.