PURPOSE: An apparatus and a method for detecting a motion are provided to detect a motion of an object with reduced amount of calculation. CONSTITUTION: An object image acquiring unit(301) acquires only an object image excluding background image using distance information of the image. A motion detection area setting unit(302) establishes motion detection domain in the obtained object image. A motion detection unit(303) detects the operation of the object by sensing the image variation within the motion detection domain.
