Abstract: The various processes of automatic low-magnification inspection of continuous casting billet were studied, and the automatic low-magnification inspection process was formulated. The automatic low-magnification inspection process involving acid etching method, scanning imaging and environmental protection device was designed. Suggestions for the design and construction of low-magnification laboratory were put forward, which could provide reference for quality management personnel of steel enterprises and engineering personnel engaged in the construction of iron and steel metallurgical laboratory.