Seasonal incident rates were examined from the 981 pigs slaushtered in southern Kang-won and distribution of lesions and histopathological examination were conducted from 231 Enzootic pneumonia affected lungs. The results obtained were summarized as follows： 1. 39.7∼50.2% of 981 slaughtered pigs showed pneumonia lesions without seasonal variation and the incidence rate of Enzootic pneumonia was 23.5% 2. The distribution of Lesions of Enzootic pneumonia lobes was observed. The right lobes were affected more frequently than the left, and the highest frequency of 79.7% being recorded in the right cardiac lobe followed by the left cardiac, right apical, intermediate, left apical, right diaphrogmatic and diaphrogmatic. 3. In histopatological observation lung lobes were forming Iymphonodulus from perivascular, peribronchiolar Iymphoid hyerplasia and it was remarkable to bronchostenosis.