As a new type of ultraviolet-visible linear array image sensor, NMOS has been applied to ultraviolet remote sensing abroad, but its research is still less domestically at present. This thesis aims at calibrating quantum efficiency of NMOS liner image sensor, which permits further application at space ultraviolet remote sensing. On the basis of standard detector provided by NIST, a high-accuracy calibration system was established to research quantum efficiency of NMOS linear image sensor. The number of photos, received by NMOS linear image sensor, was calibrated directly in this paper. And the number of electrons was calculated according to the signal processor and signal readout circuit of NMOS linear array image sensor. Then quantum efficiency of NMOS liner image sensor in 250-700 nm spectral range was calibrated. The result shows that quantum efficiency of NMOS liner image sensor reaches 34%@275 nm and 80%@550 nm. Through uncertainty analysis of quantum efficiency, the combined uncertainty is determined as 2.5%.