An apparatus is provided which assists operations required for a medical instrument. A tubular portion and a therapeutic member of the instrument are inserted through a channel of an insertion tube of an endoscope. In the apparatus, a first drive unit enables the therapeutic member to perform the desired therapeutic operations responsively to a first command signal and a second drive unit enables the tubular portion inserted in the channel to convey responsively to a second command signal. An input device is provided at which two kinds of commands are allowed to be inputted command by command. The two kinds of commands allow the therapeutic member and the tubular portion to be driven in parallel with each other. A controller provides the first and second drive units with the first and second command signals, respectively, in accordance with the two kinds of commands.
