Abstract: There is provided a target detection method and detection device that can detect a target by a simple method and configuration.

Abstract: There are provided a target detection method and detection device that include a calibration function and can maintain detection accuracy of a target irrespectively of a change (such as a temperature) in external environment. A target detection method includes: a step of calculating a quantitative value; a step of, at a first position information generation device, measuring a first target; a step of, at a second position information generation device, measuring a second target; a step of calculating a position of the second target using the first position information generation device as a position reference based on a measurement value of the first target obtained by the first position information generation device, a measurement value of the second target obtained by the second position information generation device, and the quantitative value; and a step of calibrating the quantitative value before measuring a third target using the second position information generation device.