There is a high frequency of ear diseases in Otolaryngological disorders(46%) including middle ear infections(that is perforated ear drums), 23.9%. Careful investigation of the tympanic perforation is of essential importance for determination of nature of pathology, treatment and prognosis. Five hundred cases of acute middle ear infection and 1459 cases of chronic middle ear infection were reviewed in 3 groups : first group, 1963-1965, second group, 1966-1968, third group, 1969-1971. As the statics show no drastic increase or decrease of patients could be seen. But bilateral chronic middle ear disease had a tendency to decrease. The frequency rates were 21.7% in first group, 20.6% in second group, 19.8% in third group. The unilateral chronic middle ear disease shows about 79.4% without much fluctuation in the 3 groups. Perforation of the tympanic membrane was divided into two groups, central perforation and marginal perforation. The results summerized are as follows : 1) The central perforation of the ear drum increase more than the marginal perforation. The ratio was about 9 : 1. 2) Rates of the central perforation were high and show nearly equal rates in each group. 3) The marginal perforation of the ear drum are not helpful in the determination of frequency rates in each site of ear drum perforation.