Cat scratch marks significantly impact the appearance quality and product yield of glass products, which is a defect of glass inhomogeneity. This paper discussed the causes and improvement measures of cat scratch marks defects caused by Al2O3-rich and ZrO2-rich compositions. It also introduced the concept of systematic process control, which encompassed multi-dimensional control from raw materials, batch preparation, melting, molding feed temperature system and stirring, so as to eliminate cat scratch marks defects.