A gross morphologic classification of 66 small hepatocellular carcinomas (SHCC, less than or equal to 3 cm in diameter) was made and DNA content of 30 SHCC and 26 large hepatocellular carcinomas (LHCC, greater than 3 cm in diameter) was determined by image analysis technology. The three types of SHCC are as follows: type I, noncapsule type; type II, capsule type; and type III, infiltrative type. Of the SHCC, 73.3% had diploid DNA content, and 84.6% of LHCC had aneuploid DNA content. The postoperative 5-year survival rate of patients with SHCC was 62.1%, which is higher than the rate of 27.7% of patients with LHCC. There was no correlation between tumor size and serum alpha-fetoprotein (AFP) levels. The results suggest that the period when SHCC are 3 cm in size may be important as the changes of DNA stemlines and biological characteristics would occur then. The SHCC of less than 3 cm reflect relatively benign biological behavior of early hepatocellular carcinoma and this period is the best opportunity for the clinician to get the best prognosis. Currently determination of serum AFP is still one of the possible and effective methods to early finding SHCC.