Thermoelectric material has attracted more attentions as a promising energy material in recent years. Research nowadays are devoted to improvement of figure-of-merit (zT=S2T/ρκ). Motivated by p-type AgSbTe2 compound, ternary Ag—Sb—Te has been reported as an important thermoelectric system. Although ternary AgSbTe2 compound has been considered as a candidate for thermoelectric materials with the advantages of low thermal conductivity (κp=0.6 WK−1 m−1), the relatively high electrical resistivity (ρ=7.5*10−3 Ωcm) has limited its applications. This invention disclosed brand-new Ag—Sb—Te bulk materials with very fine microstructures that nanoscale Ag2Te phase precipitate uniformly in the multi-phase matrix through class I reaction, liquid=Ag2Te+AgSbTe2+δ. Moreover, the electrical resistivity (ρ) measured by four-probe method is as low as 8.4*10−4 (Ωcm) at room temperature, which guarantees the promise of those ternary bulk materials.