A method of forming salicide, of which the characteristics is the formation of a silicon nitride layer before the source/drain being implanted with dopant. The silicon nitride layer avoid the oxygen within the oxide layer to implant into the source/drain. Thus, a better salicide is obtained. In addition, the formation of the parasitic spacers made of silicon nitride at the side wall bottom of the gate spacer increases the distance between the salicide and the junction. Consequently, the leakage current is prevented. While the silicon nitride layer is removed, the polysilicon of gate and the silicon of the source/drain are amorphized. This is advantageous to the formation of salicide without the step of ion implantation.