The invention discloses a structured light-based three-dimensional object surface reconstruction method, which comprises the following steps: calibrating a projector and a camera by using a scaling board and acquiring corresponding parameter matrixes; projecting a Gray coded image to a projection screen by the projector and capturing the Gray encoded image by the camera; and obtaining the mapping relationship between each pixel point on the projector and the position thereof on an imaging plane of the camera by preprocessing the image, preprocessing an modulated image of an object to be measured, matching scanning points in the images before modulating and after modulating and calculating a world coordinate of the surface of the object to be measured; and drawing a corresponding point cloud image according to the three-dimensional coordinate information of the object to be measured. The structured light-based three-dimensional object surface reconstruction method is widely used in three-dimensional reconstructions of various three-dimensional model surfaces in the fields of virtual reality, military simulation, industrial design, screen detection and the like relative to the technology of modelling and detecting, and has the advantages of high precision, high efficiency, low cost, easy implementation and the like.