Objective: The aim of the study was to investigate the dose effect relationship of warm distilled water to remove the exfoliated cancer cells (ECC) in peritoneal cavity in 116 cases of hepatocellular carcinoma. Methods: Positive rates of exfoliated cancer cells in 116 patients with hepatocellular carcinoma were detected before and after the removal of the tumor. The 43 to 45 ℃ distilled water was used by 1 500 ml/time before closing the abdomen, and then 37 ℃ sterile normal saline 200 ml was used for peritoneal lavage and collected for exfoliated cancer cell detection. Results: Positive rates of ECC had no significant difference before and after resection in groups with tumor diameter ≤10 cm (all P>0.05); positive rates of ECC were significantly increased after tumor resection in groups with tumor diameter>10 cm (≤15 cm, >10 cm, P=0.044; >15 cm, P=0.033). With the increase of tumor volume, ECC positive rates were significantly increased after resection (P<0.001), and the residual rate increased after washing; the residual rates was significantly decreased with the increasing of irrigation times in groups with tumor diameter>10 cm (≤15 cm, >10 cm, P=0.002; >15 cm, P=0.001), and undetectable after four times washing. With the increase of irrigation times, the residual rates were not significantly decreased (all P >0.05) in groups with tumor diameter ≤5 cm, but no residue was detected after three times of washing. Conclusion: The volume of irrigation needed to eliminate the ECC in the peritoneal cavity during the operation of hepatocellular carcinoma is significantly correlated with the tumor size.