Five hundred and thirty-three cases (males 346, females 187; average age 58.9) of early colorectal carcinomas including 482 cases with single lesion and 51 cases with synchronous multiple lesions diagnosed at Cancer Institute Hospital in Japan from Jan. 1991 through June. 1995, were analyzed clinicopathologically. Early carcinomas accounted for 45.6% among all colorectal carcinomas. The total number of lesions was 622. Tumors were localized in the sigmoid colon in 42.8% of the 622 lesions and in 22.9% in the rectum. Macroscopically, 31.0% of the tumors were of pedunculated type and 29.3% was of subpedunculated type. With the growth of polyps, the frequency of malignant changes increased. Therefore, polyps should be considered as premalignant lesions and treated early.