A temperature measurement apparatus includes a light source; a first splitter that splits a light beam into a measurement beam and a reference beam; a reference beam reflector that reflects the reference beam; an optical path length adjustor; a second splitter that splits the reflected reference beam into a first reflected reference beam and a second reflected reference beam; a first photodetector that measures an interference between the first reflected reference beam and a reflected measurement beam obtained by the measurement beam reflected from a target object; a second photodetector that measures an intensity of the second reflected reference beam; and a temperature calculation unit. The temperature calculation unit calculates a location of the interference by subtracting an output signal of the second photodetector from an output signal of the first photodetector, and calculates a temperature of the target object from the calculated location of the interference.