The hydrogenation behaviors of tantalum metal and the dehydrogenation behaviors of tantalum hydride powder have been studied in this paper. The results of hydrogenation show that the tantalum ingot is easy to form a barrier layer on its surface during hydrogenation, which can be broken by increasing the pressure of hydrogen and using hydrogenation-dehydrogenation-hydrogenation (H-De-H) process at the same time. Finally, tantalum hydride powder with hydrogen content of 0.427 wt % was obtained. The dehydrogenation results show that TaH0.1 and Ta phases begin to appear at 500 °C under vacuum condition, and complete dehydrogenation can be achieved at 600 °C for 1 h. Under the condition of hydrogen atmosphere, the presence of H2 has an inhibitory effect on the dehydrogenation reaction, and it is most obvious when the temperature is 700 °C.