Detection of the cancer as early as possible is very important to improve survival. Morson had described early colorectal cancer as colorectal cancer confined to mucosa and submucosa without regard to metastasis to lymphnodes. To identify any distinctive characteristics of early colorectal cancer, we studied 1,274 cases of colorectal cancer who were operated at Yonsei University, Sever- ance Eiospital, during the 20-year period between Jan. 197l and Dec. 1990. The incidence of early colorectal carcinoma was 2.1%. (27/1,274 cases). Rectal bleeding was the most frequent presenting symptom in patients with early colorectal cancer. Rectum was more prevalent site of the tumor in the early colorectal cancer group than the advanced group (77.8%. VS. 50.5%, p<0.01). The most frequent macroscopic type of early colorectal cancer was pedunculated polypoid (37.1%), followed by subpedunculated polypoid (14.8%), sessile elevated (14.8%), elevated with central depression (25.9%), and flat elevated (7.4%). Of 27 early colorectal cencers, cancer was confined within mucosa in 9 cases (33.3%) and extended to submucosa in 18 cases (66.7%). The rate of lymphnode metastasis was 3.7%. In 15 (55.6%) of 27 cases of early colorectal cancer, the adenomatous component were found in the tumor tissue. Hisetologically well differentiated form was much more frequent in early colorectal group than that of the advanced group (40.7% VS. 20.0%, p< 0.01). The cumulative 5-year survival rate was significantly higher in the early group than that of the advanced group (90.9% vs. 54.7%, p<0.05).