The Cornell Medical Index is a self-admininistered instrument that collects a large body of Significant medical and psychiatric data. The questions on the C.M,I. are arranged in sections headed by letters of the alphabet, questions in each section being related. There are two forms of the C.M.I., one for men and the other for women. Both are identical except for six questions in the genitourinary section. The present study is an attempt to clarify some existing discrepancies in physical and mental complaints of teachers. The Study was Conducted by the Author from March to September, 1975 on the physical as well as mental Complaints of teachers through applying Cornell Medical Index towards a total of 400 teachers residing in Seoul City. The findings from this study can be outlined as follows: 1. Significant differences are found between male teacher’s complaints and female teacher’s complaints. The total average complain Index was 44.2: male teacher’s was 41. 5 and female’s was 47.2. 2. It is similar to differences of complaints between elementary teachers and secondary school teachers. 3. Significant difference are found between Senior teacher's complaints and junior teacher’s complaints. 4. Significant Correlation between M-R and C-I-J items.