The invention discloses a three-dimensional target for binocular or multi-view vision dimension measuring. The three-dimensional target adopts the structure of a regular cube, and four side surfaces of the three-dimensional target are measuring surfaces. In a measuring process, a measuring probe is fixedly mounted in a connector on the lower bottom surface of the three-dimensional target; when the three-dimensional target is placed in a binocular or multi-view vision system, the measuring head of the measuring probe is in contact with a measured point, an image of the three-dimensional target is obtained; through image processing, a measuring surface used for calculation is confirmed; information of coding points on the measuring surface is separated, and a coding value and the three-dimensional coordinate of a central locating point are calculated; then, the three-dimensional coordinate of the measured point is calculated according to the distance relation between the central locating point and the measuring head. The three-dimensional target has the benefits that the information of the measured point can be obtained as long as the three-dimensional target is positioned within a camera view field range, and then such hidden geometrical characteristics as deep holes, grooves and complex curved surfaces on measured mechanical parts can be accurately measured; the three-dimensional target is applicable to manual or automatic measuring of the sizes, tiny holes, grooves and complex curved surfaces of various mechanical parts.