The invention provides an instrument machine tool provided with an infrared detection unit. The instrument machine tool comprises a workpiece clamping mechanism and a tool clamping mechanism, wherein an infrared transmitter and an infrared receiver are arranged on two sides of the tool clamping mechanism; the tool clamping mechanism comprises a positioning shaft sleeved with a tool plate, at least two tool movement grooves are formed in the tool plate, and tools are arranged in the tool movement grooves in a penetrating manner; tool pushing mechanisms are arranged in the tool movement grooves and provided with tool locking/automatically unlocking mechanisms, tool returning mechanisms are arranged in the tool movement grooves, and the tool pushing mechanisms provided with sliding guide rail mechanisms and push sliding driving mechanisms; a tool capture mechanism is arranged on the positioning shaft. The instrument machine tool has the beneficial effects as follows: whether a tool is in place or not is detected automatically by the aid of infrared rays, and time and labor are saved; multiple groups of tools are arranged in the tool plate in a hidden manner and are safe to use, various actuating mechanisms for tool replacement are reasonably arranged, and the tool replacement action is stable and smooth.