ObjectiveTo investigate the effect of lentinan on the therapeutic effect of chronic hepatitis B patients treated with adefovir (ADV).MethodsSixtysix patients with chronic hepatitis B were randomly divided into  lentinan plus ADV treatment (34 cases) and only ADV  treatment (32 cases) groups, all patients received treatment  for 12 months. Patients’ normalization of the alanine aminotransferase(ALT), negative conversion rate of   HBeAg, HBeAg/antiHBeAg seroconversion rate, serum HBV DNA decreasing levels and side effect were observed. ResultsAt 6 and 12 month of treatment, negative seroconversion rate of HBeAg in combination treatment group was 35.48% and 61.29% respectively, which was significantly higher than 10.34% and 34.48% of single treatment group (χ2=5.29, P=0.02; χ2=4.31, P=0.04, respectively); At 12 month of treatment, HBeAg/antiHBeAg seroconversion rate  in combination treatment group was 48.39%, which was significantly higher than 24.14% of single treatment group (χ2=3.79, P=0.05). At 1,3,6 month of treatment, normalization of ALT in combination group was 54.84%, 67.74% and 77.42% respectively, which was significantly higher than 24.14%, 41.38% and 51.72% of single treatment group (χ2=5.88, P=0.02; χ2=4.21, P=0.04; χ2=4.35, P=0.04 respectively).  At 1,3,6 month of treatment , serum HBV DNA negative conversion rate in combination group was 41.94%, 61.29% and 70.97% respectively, which was significantly higher than 13.79%, 34.48 and 44.83% of single treatment group(χ2=5.84, P=0.02; χ2=4.31, P=0.04; χ2=4.21, P=0.04, respectively). Both groups had no side effect. ConclusionLentinan can  enhance the shortterm therapeutic effect of chronic hepatitis B patients treated with ADV，especially the negative conversion rate of HBeAg and HBeAg/antiHBeAg seroconversion rate; ADV can efficiently decrease the replication levels of HBV DNA.