Abstract:The effects of B2O3 with w=0.5% to 3.0% on the structure and microwave properties of Ba(Mg1/3Ta2/3)O3(BMT) ceramic has been investigated. It has been found that B2O3 doping can improve the BMT microwave ceramic sintering. When w(B2O3) is equal to 1%,the densification sintering temperature of BMT ceramic has been reduced to 1 200 ℃,the apparent density ρ is equal to 7 306 g/cm3,the relative density is 95.7%.The BMT microwave ceramic system has good microwave dielectric properties as follows:εr=22.08, the quality factor Q·f=88 000 GHz(10 GHz),the coefficient of frequency to temperature τf=3.3×10-6/℃.