Parallax computation method and device

An embodiment of the invention provides a parallax computation method and device. The parallax computation method comprises the following steps: according to a parallax image of a first image frame shot by a stereo camera at the previous moment, selecting parallax-reliable reliable pixel points in the first image frame; predicating pixel points corresponding to the reliable pixel points in a second image frame shot by the stereo camera at the current moment; determining at least a part of the reliable pixel points as selection pixel points; for each selection pixel point, determining a parallax computation range of the pixel point corresponding to the selection pixel point in the second image frame shot by the stereo camera at the current moment; and according to the parallax computation range of each selection pixel point, calculating parallax of the selection pixel point in the second image frame.