A method for 3-D recursive search motion estimation is provided to estimate a motion vector for a current block in a current frame. The method includes the following steps. First, provide a spatial prediction by selecting at least one motion vector for at least one neighboring block in the current frame. Then, provide a temporal prediction. After that, estimate the motion vector for the current block based on the spatial prediction and the temporal prediction. The temporal prediction is obtained by selecting at least one most frequent motion vector from a plurality of motion vectors for a plurality of blocks in a corresponding region of a previous frame, wherein the corresponding block encloses a previous block which is location corresponding to the current block in the current frame.