The invention provides a door region identification method, a door region identification system and a cleaning robot. Through obtaining a raster map in the home environment, an irrelevant region and aregion to be treated are obtained by segmenting the raster map, then the characteristic value of the region to be treated is obtained to obtain a first region and a second region, region separated signs are conducted, preset parameters of a door region are obtained, matching modules are generated according to the preset parameters, and finally, a whole scan is conducted by using the matching modules and the signs to identify the door region. According to the door region identification method, the door region identification system and the cleaning robot, through optimizing internal arithmetic,without the help of virtual wall equipment, the mobile robot can use the characteristic value of the door region to match data, finally, the position of the door region is identified through the matching modules, region separated cleaning can be conducted by the mobile robot through taking the position of the door region as a boundary, the region separated cleaning autonomously is achieved, the manufacture cost is saved, and user experience is improved.