A grinding package fitted on robotic arm includes a main body, a pneumatic motor, a bridging part and a grinding tool. The main body is formed with a first space, a second space, a communicating hole communicating the first space to the second space, a connecting wall within the first space, an intake channel, an exhaust channel, openings of the first space and the second space respectively located on each of two parallel sides of the main body, the connecting wall having a ventilation hole. The pneumatic motor includes a motor body within the first space, and a transmission shaft connected to the motor body while extended from the second space through the communicating hole. The bridging part is combined with the main body and the robotic arm, the bridging part closing off the first space, the grinding tool facing the second space and being joined to the transmission shaft.