The invention discloses a noncontact surface measuring three-coordinate device, comprising a bottom plate, a gantry slidingly mounted on the bottom plate longitudinally, a slide block slidingly mounted on a gantry beam in laterally, a CCD camera lens and a projector lens fixed to the slide block, and a drive system for driving the gantry and the slide block to slide. The drive system includes a motor, a longitudinal transmission mechanism for driving the gantry to slide, and a lateral transmission mechanism for driving the slide block. The rotating shaft of the motor is drivingly connected with the longitudinal transmission mechanism. The lateral transmission mechanism is used for interlocking the slide block with the gantry. The noncontact surface measuring three-coordinate device is simple in driving structure, low in cost, high in control precision, beneficial to improvement of measurement efficiency, and suitable for noncontact surface measurement, and achieves direct online measurement. Fast measurement speed and convenient operation are obtained by a digital grating. 3D point cloud is directly obtained by coordinate transformation, no data splicing is required, and high measurement accuracy is obtained. Easy information integration and management and intelligent detection are realized.