The invention provides a barrier inspection method, system and robot, and relates to the technical field of barrier detection technology. A three-dimensional space point cloud of a target region is constructed according to collected deep information of a camera; processing is conducted on the three-dimensional space point cloud to obtain the rotary angle of the camera; the three-dimensional spacepoint cloud is rotated according to rotary angles, and ground point cloud is extracted from the rotated three-dimensional point cloud; a barrier point cloud is obtained from the rotated three-dimensional point cloud according to the ground point cloud to obtain barrier detection information. According to the method, modeling is conducted by using point cloud space by collecting deep information, the pitch angle of the camera can be obtained, and demands of camera installing angle and factory leaving installing technique are effectively prevented.