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In this study, spherical tantalum powder fabricated by radio frequency plasma spheroidization system was used for selective laser melting densification. Through optimizing the processing parameters, the fully dense Ta sample was obtained at the scanning speed of 650 mm/s and the laser power of 240 W. Attributed to the high sphericity, the Ta samples performed better densification behavior and surface quality. Microstructure characterization showed that equiaxed grains and columnar structure were present in the top- and side- views, respectively. The EBSD results revealed a <111> preferred orientation along the building direction. The maximum microhardness and the ultimate tensile strength reached 296.2 Hv and 697 MPa, respectively. A significantly improved ductility with elongation of 28.5% was achieved for the dense sample.