A miniature laser-guided measuring robot (LGMR) has been developed based on a novel theory “laser beam moving and spherical mounted retro-reflector (SMR) tracking” instead of the traditional method “SMR moving and laser beam tracking”. A systematic algorithm of generating optimal inspection planning based on CAD-directed model is proposed for LGMR to inspect free-form surfaces. The method integrated techniques from feature extraction, inspection path planning to generate the movement orientation, position and optimal distance for LGMR. Also, it automatically generates a consistent and efficient inspection process that can avoid the unnecessary trials in manual operations and reduce inaccuracy and inconsistency due to different operators. A free-form surface of automotive body is used to test the CAD-directed inspection planning which is generated from the proposed methods. The experiment results have demonstrated that the inspection planning can be integrated to the LGMR and generated automated scanning process under automaticity and accuracy constraints.