A method and apparatus to segment a motion area in real-time to detect motion in a surveillance camera system are provided. The method includes updating a background image by using a previous input image from among an input image sequence, generating a difference image between a current image of the image sequence and the background image, generating a second function to minimize a first function including regularized energy in the motion area of the difference image and regularized energy in an area without motion of the difference image and segmenting the motion area based on the second function. Therefore, while noise is removed, the motion area is segmented accurately and rapidly even in a low illumination environment so as to detect a moving object.