Abstract:High density GH3536 ni-based superalloy block specimens were prepared by laser selective melting method, and the microstructure and crystal orientation of GH3536 alloy were analyzed. The results show that with the increase of laser energy density, the density of the formed sampleSincreasedSatSfirstSandSthenSdecreased, When the laser energy density is 180~230J.m-1, the density reaches over 99.55%. The structure has obvious anisotropy, the microstructure perpendicular to the construction direction presented a checkerboard morphology, and most of the grains were equiaxed (the length-diameter ratio was 1.828μm) and were refined (dmean=11.226μm), In particular, the grain size in the lap area of molten pool is finer (less than 5 m). Parallel to the construction direction was the fish scale morphology, most of which were columnar crystals (the length-diameter ratio was 2.831μm), with a larger grain diameter (dmean=25.964μm). Simultaneously, SLM processed GH3536 nickel-based superalloy has obvious preferential orientation. On the cross section, the grain has a strong orientation < 100 > orientation, which is cubic texture {100}<001> perpendicular to and parallel to the construction direction. In addition, grain growth in SLM solidification has a significant effect on the evolution of crystal orientation in grain, the crystal orientation in the deformed grain of the longitudinal section does not change obviously, while the crystal orientation in the deformed grain of the longitudinal section changes obviously, this is due to the extremely high temperature gradient and rapid cooling rate (105K/s) of SLM.