Abstract: Quick frozen instant rice can maintain the flavor of fresh rice. Its processing and frozen storage conditions influence sensory quality of quick frozen rice. In most studies, the temperature range of quick frozen instant rice was 4 ~ -18℃, and the quality change of frozen rice at low or ultra-low temperature was far from clear. As the temperature of the refrigerated product can reach -30 ℃ at present, the rate of product quality change under low temperature has practical research value. In this experiment, the processing conditions of quick-frozen instant rice were optimized by single factor test and orthogonal test, to achieve the best sensory quality. Freezing storage temperatures of -18 ℃ and -30 ℃ freeze storage every 3 weeks for 12 weeks were set, and the following parameters were determined: water content, texture characteristics, water migration, short-range ordering and crystallinity of starch molecules by UV Spectrophotometer, Texture Analyzer, Low Field NMR, Fourier Infrared Spectrometer and X-Ray Diffractometer. The quality changes of quick-frozen instant rice during frozen storage were studied from two aspects of macro quality and microstructure. The results showed that the best technological conditions for the preparation of quickfrozen instant rice were as follows: soaking temperature was 50 ℃,cooking time was 35 min and cooking pressure was 60 kPa. During frozen storage, the hardness and chewiness of rice increased, the adhesiveness decreased, and the sensory quality decreased; Water loss, strong bound water migrated to free water; The short-range order of starch molecules increased by 6. 49% and 5.74% respectively when frozen at-18 ℃ and -30 ℃,and the crystallinity increased from 14.98% and 14.02% to 31.61% and 25.56% respectively. The quality of quick-frozen instant rice was deteriorated with the extension of frozen storage time, and reducing the frozen storage temperature from-18 ℃ to-30 ℃ could effectively delay the rate of quality change of quick-frozen instant rice, which was conducive to the storage of quick-frozen instant rice and the extension of product shelf life.