Diamond is a superhard and multi-functional material with excellent properties. Synthetic diamond can own unique properties by doping. Boron-doped diamond has both conductive characteristics of p-type semiconductor and excellent physical and chemical properties. It has wide application value in national defense, medical treatment, exploration, scientific research and other fields. Based on boron-doped diamond and boron co-doped diamond single crystals synthesized by high pressure and high temperature (HPHT) method in our laboratory, the synthesis and properties of boron-doped diamond, boron-hydrogen co-doped diamond and boron-nitrogen co-doped diamond are discussed. The influence of different additives on the synthesis properties of the synthetic diamonds through the optical and electrical characterization are analyzed, which provides some ideas for further synthesizing high-performance semiconductor diamonds.