In this paper,a novel roll-to-roll imprint process is proposed to fabricate gratings in large area. The key challenges in roll-to-roll imprint process,such as the roller mold preparation,imprint system,misalignment of imprint roller and backup roller,and also the imprint pressure,are investigated. Various gratings with different periods and profiles are obtained by the roll-to-roll process. To calibrate the measuring ability of the self-made grating by imprint,a calibration system is built with a dual-frequency laser interferometer. By the calibration,the self-made gratings can achieve ±4μm accuracy in 45mm measuring distance. The key challenges in roll-to-roll imprint process, such as the roller mold preparation, imprint system, misalignment of imprint roller and backup roller, and also the imprint pressure, are investigated. Various gratings with different periods and profiles are obtained by the roll-to-roll process. To calibrate the measuring ability of the self-made grating by imprint, a calibration system is built with a dual-frequency laser interferometer. By the calibration, the self-made gratings can achieve ± 4μm accuracy in 45mm measuring distance.