The invention discloses a material-discharging mechanical arm of a manipulator device, which includes a frame, a mechanical arm, a clamping mechanism, and a total power drive mechanism. The total power drive mechanism includes a first rotation drive assembly, a second rotation drive assembly, a third rotation drive assembly, and a The drive assembly, the fourth rotation drive assembly, the first transmission assembly, the second transmission assembly, and the third transmission assembly, the clamping mechanism includes a clamping finger, a first clamping link, a second clamping link, and a lifting bracket , a first rotary cylinder, a second rotary cylinder, and a nut sleeve, the first rotary drive assembly, the second rotary drive assembly, the third rotary drive assembly, and the fourth rotary drive assembly are installed above the frame , one end of the mechanical arm is rotatably connected to the upper part of the frame, and one end of the mechanical arm is connected to the first rotary drive assembly. The invention has a stable and reliable structure, realizes automatic transfer or handling of objects without manual participation, saves labor costs, and improves production efficiency.