A processing device includes a remote-controllable device position information acquisition unit that acquires information on a position of a remote-controllable device, a relative positional relationship information acquisition unit that acquires information on a relative positional relationship between a terminal device transmitting instructions to request control regarding the remote-controllable device via another device having a communication function not included in either the processing device or the remote-controllable device by communicating with the other device, and the remote-controllable device, a determination unit that determines if each condition regarding the position of the remote-controllable device and a condition regarding the relative positional relationship is satisfied on the basis of the acquired information, and determines whether to permit the terminal device to perform the control regarding the remote-controllable device according to a result of the determination, and a control unit that performs control.