A new method of actualizing grating non-diffracting structured light (GNSL) is proposed. The GNSL holds characters of long focal-depth, narrow strip-width, steady light field and constant light intensity in certain rang etc. Based on precise triangular-section prism, an optical system is designed and actualized experimentally. With theory analysis and calculation to the optical system, the distribution of the light intensity is simulated in non-diffracting range. Experiment results show that simulation is in good agreement with the theory calculation. According to system parameters, GNSL with 18um strip-width and 57cm non-diffracting range is produced in experimental system. Compared with traditional projected light source, GNSL has advantages of high resolution and high precision in the application of three dimensions (3D) shape measurement. By using GNSL, matching ambiguity could be reduced.