The expression of epidermal growth factor receptor (EGFR) was studied immunohistochemically in 92 colorectal carcinomas: 21 early and 71 advanced. EGFR immunoreactivity was detected in 15 cases (16.3%) of colorectal carcinomas. All EGFR-positive cases was advanced carcinomas, while no EGFR immunoreactivity was found in early carcinomas. EGFR-positive cases were macroscopically 3.4 type and more than 2 cm in diameter. No significant correlation of EGFR expression with tumor location, stage, lymph node metastasis, degree of differentiation, and prognosis was found. All EGFR-positive cases was synchronous positive for the expression of EGF. These results suggest that EGFR may play an important role in tumor progression in cooperation with EGF.