One year ago, we reported the status of chronic otitis media among primary school children in Chungnam area as a preliminary survey. This is the second report which was undertaken in the another rural and seaside areas of Chungnam province from December, 1980 to February, 1981. Total number of 13,047 primary school children(male 6,528 and female 6,519) consisting of 7,500 from 4 primary schools in north-west rural area and 5,547 from 8 primary schools in north-west coast were examined by means of otoscopy. Like the previous study, only the eardrum perforation cases were regarded as COM patients in this study. The results were as follows : 1) Overall prevalence rate of COM was 0.820%(107/13,047) and there were no significant differences between ages and sexes. 2) The prevalence rates in each area were 1,010% in north-west coast and 0.680% in north-west rural area. 3) The prevalence rates in each socioeconomic group were 0.336% in higher group, 0.401% in middle group and 1.840% in lower group, i.e. much more prevalent in lower group than in the other groups. 4) The prevalence rate in the groups classified by educational level of parents, was relatively higher in the group with poorly educated parents(1.004% with father ; 0.902% with mother) than in the group with highly educated parents(0.541% with father ; 0.637% with mother). 5) On duration of COM, 55.1% of cases had history of 2-5 years, 19.6% had over 5 years, 16.8% had 1-2 years and 8.4% and below 1 year. 6) On otoscopic examination, central perforation were observed in 86.8%, total perforations in 9.1% and marginal perforations in 3.3%.