Abstract: Compared with rectangular and sinus oidal grating, sawtooth grating has higher diffraction efficiency. It can be fabricated by holographic ion-beam etching and single point diamond turning (SPDT) technology. First, the errors in fabrication process with the two methods were introduced. Secondly, effect of these fabrication errors on the diffraction efficiency of sawtooth grating used in NIR and long-wave infrared imaging spectrometer was analyzed. It is indicated that blaze angle error, vertex angle error and burin radius are the main factors in diffraction efficiency. This provides a theoretical foundation and instruction for fabricating high-quality grating used in imaging spectrometer.