A biological measurement apparatus includes: an endoscope including a treatment instrument insertion channel provided inside an insertion portion a pump that delivers water into the treatment instrument insertion channel an optical system, etc., that guide light from a light source that emits light in a predetermined wavelength band into the water delivered into the treatment instrument insertion channel and a spectroscope that detects return light resulting from the light passing through the water, falling on and being reflected by an object and returning while passing through the water when the water is delivered from the pump.
