ObjectiveTo observe intervention effect of Shenlingcao oral liquid on asymptomatic chronic hepatitis B virus carriers (AsC). MethodsA self control before-after trial was conducted in the First Affiliated Hospital of Jiangxi University of Traditional Chinese Medicine and the Ninth People's Hospital of Nanchang City from November 2011 to May 2012. A total of 64 AsCs were treated by Shenlingcao oral liquid (1 bottle/d, 200 mL, once daily for 6 months). Serum HBV viral load, six specific serum markers of HBV and 11 liver function index were tested and recorded before and at the 1th, 3th, 6th months of the treatment. Analysis of variance of repeated data was conducted. ResultsAfter one month of the treatment, 35/57 (61.40%) AsCs' serum HBV-DNA loads decreased, 1 log decrease was observed in 15 cases, 2 log decrease was observed in 4 cases, and decrease under the detection limit was observed in 12 cases. 41/57 (71.93%) AsCs' serum HBV-DNA loads decreased after 3 months of treatment, 1 log decrease was observed in 21 cases, 2 log decrease was observed in 5 cases, and decrease under the detection limit was observed in 15 cases. 31/49 (63.26%) AsCs' serum HBV-DNA loads decreased after 6 months of the treatment, 1 log decrease was observed in 19 cases, decrease more than 2 log was observed in 7 cases, and decrease under the detection limit was observed in 12 cases. The serum HBV viral loads at different time points of the treatment were significantly different (P<0.001). As medication time went, AsCs' serum HBV viral loads presented a decrease trend after taking Shenlingcao oral liquid, especially obvious at the 3th month. ConclusionShenlingcao oral liquid could help promote AsCs' ability of clearing virus and controlling serum HBVDNA loads.