The invention discloses a vision image mosaic system and a method of a mobile robot, suitable for a mobile robot platform for binocular vision. The system includes a robot image acquisition module, animage mosaic system processing module and a wireless image display module, wherein, the image mosaic system processing module comprises a preprocessing module, a boundary location module, a superposition area image registration module, an image deformation fusion module, an image smoothing module. Through the module, the images collected by the robot binocular can be preprocessed, the boundary line positioning, the image registration of the overlapping region, the image deformation fusion and the image smoothing processing, and high-quality mosaic images can be obtained. The system and the method greatly broaden the vision of the robot, and can better complete the purposes of movement, positioning, recognition, and the like.