In order to improve the forming accuracy of the selective laser melting part, 316L stainless steel parts with different sloping angles were fabricated by selective laser melting equipment. The influence of sloping angle on the forming accuracy of 316L stainless steel was studied by density measurement, forming dimension measurement and surface roughness measurement. The results show that with increasing the sloping angle, the density of SLM samples decreases firstly, and then increases to the maximum value of 99.82% at 0°. The dimension error in the x and z directions increases first and then decreases, while the dimensional error in the y direction changes in the shape of "W". The surface roughness of A and C plane increases firstly and then decreases, the upper surface roughness of the sample is the minimum at 0° and 90°, which is 6.79 μm and 6.43 μm, respectively. The surface roughness of the B plane is basically the same.