The microstructures and thermoelectric properties of AgSb1-xGaxTe2 (x=0-0.2) alloys prepared by spark plasma sintering (SPS) were examined. Results show that the AgSb1-xGaxTe2 alloys possess the same crystal structure with AgSbTe2, and formed secondary phase AgGaTe. After the alloy was doped with Ga, Seebeck coefficients were higher than that of the reference sample without Ga doping, but the thermal conductivity was lower than that of AgSbTe2. When x=0.1, i.e. the alloy was AgSb0.9Ga0.1Te2, the maximum ZT was 0.29 at 375 K, which was approximately 0.08 higher than that of AgSbTe2.