Selective laser sintering (SLS) is one of an additive manufacturing that can produce a 3D part a layering method, this technique uses a powder to create a 3D part by using a laser to fuse the powder. Layering method is used to build the 3D part by fusing the powder layer after layer until complete the part. In this paper will calculate better depth to reduce defects that happen during the printing process. Increase or decrease a temperature that apply on a powder will produce defects in the part. Therefore, the layer depth will calculate and study to reduce the defects during the printing process, simulation process by using ANASYS program will use to check a thermal distribution of temperature on the powder. In addition, laser speed on the powder will consider during the simulation process and determine the best speed for the laser on the powder.