Abstract: A new technique of using Hough transform for shape detection is proposed, which we call the Polar Coding Multiple Resolution Hough Transform (PCMRHT). In the PCMRHT, both template and image are coded into 1D sequences in polar coordinate representation. This technique simplifies the mapping operation of Hough transform, and also, makes it possible to develop a multiple resolution representation of bob image and parameter spaces, thereby enabling the task of detection to be efficiently performed at successively higher resolution levels in a tree-search-like manner. Experiment results are also presented.