Abstract: In order to realize the coordinate measurement of hidden parts in the large-scale space, a combined non-contact measurement system which combined attitude angle sensor, angle encoder, laser rangefinder and total station, was proposed. A mathematical model of the measurement system was established. The calibration target was designed and the measurement system was calibrated. For the measurement system, a calibration method based on the weighted least squares was proposed and the weight value was determined according to the spatial distribution of the control points. The precision of the combined system was verified by comparing the error of the same test point between the spatial coordinate measured directly by the total station and that of measured indirectly by the combined system. Experimental results show that the measurement system could expand the scale and achieve reliable precision during combined measurement and the measurement error of the weighted least squares method is smaller than that of the general least square method.