The surface of SiC was plating mental of Ni, and the effect of pH of plating bath on plating speed, phase composition and microstructure was investigated. The results show that the SiC powders have no plating mental of Ni and no reaction can occur when the pH below 8 . 5 . When the pH value is between 10 and 11 , the weight gain of powders close to the theoretical value, the Ni peaks in X-ray diffraction patterns of powders is relatively strong and the substrate is covered of Ni plating completely . When the pH value is above 11 , the gas production is becoming more pronounced and the reaction speed accelerates significantly with the increased of the pH value, the time of the plating bath changed from dark blue to colorless is obviously shortened . The double-plating is be carry out when the pH value is between 10 and 11 , the plating becomes more thickness and has a uneven surfaces, the sizes of Ni particle are not uniform.