To improve the drilling efficiency of diamond bits in reinforced concrete and strong abrasive rock， a pre-alloyed Fe powder with high wear resistance and cold pressing molding ability was selected for the matrix. The formulas of Fe matrix were designed to research the effect of Fe-based pre-alloy powder， Cu， Ni and Co on the matrix and drilling properties of the diamond drill bits. Analysis was conducted of the tensile strength， three-point bending strength and hardness of the sintered samples of different formula， and the ruptures of the sintered samples were investigated with SEM. The drilling efficiency and life of the drill bits was field tested. The effects of heat insulation time on the mechanical properties of Fe-based matrix were also analyzed. The results showed that Cu， Ni and Co had a great influence on the bending strength and hardness of the Fe-based matrix， and the mechanical properties of the Fe-based matrix can be improved when the insulation time was 5min.