1. A region-based motion detection method capable of detecting motion of an object displayed on a frame, the region-based motion detection method comprising: dividing a current frame into a plurality of first template arrays; dividing a first reference frame into a plurality of second template arrays; acquiring characteristic values of one of the plurality of first template arrays and a corresponding second template array of the plurality of second template arrays; comparing the characteristic value of the foresaid first template array with the characteristic value of the corresponding second template array by matching process; and executing motion detection of the object displayed on the current frame according to a result of the matching process.