A distance measurement apparatus comprises an acquisition section which counts time between a first timing when an output of a photodiode built in a semiconductor laser exceeds a first threshold value because a laser element of the semiconductor laser starts to output laser light and a second timing when the output of the photodiode exceeds a second threshold value higher than the first threshold value because the laser light is reflected by a measurement object and returns to the laser element, and acquires the counted time as flight time of the laser light from a moment when the laser light is output to a moment when the laser light is reflected by the measurement object and returns to calculate a distance from the laser element to the measurement object or displacement of the distance.