The cutting edge angle of a knife is an important factor, affecting the cutting performance. Therefore, it is necessary to measure the cutting edge angle of a fresh fish knife comparing to cutting performance. This paper described a new measuring system of cutting edge angle using a laser light, and the measuring precision. The results are summarized as follows.
1. The cutting edge angle of seven single-edge knives of three kinds, was not uniform, which might be the result of handwork.
2. The influence of laser light beam diffusion on measuring precision is very small. The measurement error was about 0.1°.
3. It is possible to use the method for sampling inspection in the production process, and it makes a major contribution to the uniformity of the products.