The additive manufacturing of metal parts provides new opportunities to freely design of molds with conformal cooling channels, which enhances the productivity of injected plastic parts. In contrast to this manufacturing process, the surface quality of laser sintering parts is limiting the application of such technology on mold manufacturing. This work intends to investigate the surface roughness of maraging steel 300 samples produced by direct metal laser sintering (DMLS) and post-processed with end milling. Based on a set of experiments, combining different laser sintering build directions and milling process the measurement of the resulting surface roughness expresses how these process parameters impact on the final surface quality.