A measurement endoscope system includes: an image pick-up device, an endoscope insertion portion to which a plurality of stereo measurement optical adaptors and a normal measurement adaptor are detachably attachable, a control unit for accommodating the endoscope insertion portion, a face mounted display for stereoscopically viewing a normal endoscope image or stereoscopically viewing the endoscope image as a pseudo stereo image, and the like. The control unit includes a CPU for controlling the execution of various functions based on a main program, a ROM, a RAM, a PC card, a USB port, an RS-232 port, an audio signal processing circuit, and a video signal processing circuit. The control unit can be connected externally to a PC. The measurement endoscope system allows taking image re-measurements under a correct measurement environment simple operation, with the re-measurements being performed promptly without consideration of the measurement environment. Thus, the operability of the system is improved and greatly expedited.