A series experiments are conducted to study the selective laser melting（SLM） process of refractory metal tantalum. The single pass,single layer and bulk experiments with different laser powers,scanning speeds and scanning spaces are explored. The experimental results show that the optimum SLM parameters for tantalum are laser power of 300 W and scanning speed of 50 mm/s. According to the different degrees of cracking on the tantalum layers,the heat conduction and the accumulation of internal stress in SLM process are analyzed qualitatively. Finally the cubic tantalum is successfully fabricated and its microstructure and component distribution is characterized by SEM and EDX.