A detection device that includes a light emitting part that outputs coherent light, a first light receiving part that generates the first detection signal according to a light reception level of the coherent light output from the light emitting part and passing through an artery of the measurement site, and a second light receiving part that generates the second detection signal according to the light reception level of the coherent light output from the light emitting part and passing through the artery, wherein the light emitting part, the first light receiving part, and the second light receiving part are provided on a detection surface facing the measurement site and located on a straight line, and are located at an equal distance from the light emitting part on opposite sides to each other with the light emitting part in between.
