Internal surface condition of mould will affect the metalworking product quality after the casting process. Traditional visual inspection devices cannot keep working when the temperature is beyond 70°C. A vision inspection system protected by a cooling housing was introduced in this paper. The system was designed to provide quality images for defect inspection needs while enduring high temperatures. Illumination strategy consisting of lighting position and orientation was developed to cover 360° inner surface and accentuate defects in images. The housing protected vision system would be motorized into the mould to user-specified position and capture images with trigger mode. Developed algorithm would process images and output inspection results in the backend. Overall inspection of 2-meter mould could be completed within 100 seconds. The developed vision system is fast and low-cost, which can be easily implemented on site and provide defect inspection for cast mould with high temperature.