The spectroscopy, petrology, and sequence stratigraphy were used to study and analyze the cores of the QZ16 Quemocuo Formation in the Maqu area of the Northern Qiangtang Basin, for more accurately classify and identify the stratigraphy and sedimentary facies of the Quemoco Formation. Methods:The infrared spectral reflection technology was used to scan the cores of QZ16 well, analyzes the relative content curve of minerals by using the principle of sequence stratigraphy, well logging and petrology, and identifies the sedimentary facies in combination with the principle of sedimentology.Results: Quartz, gypsum, clay minerals and carbonate minerals were identified and their relative content curves were obtained. According to the test results, the stratum is divided into eight small layers, including Que1 Member: Que1-1, Que1-2, Que1-3; Que2 Member: Que2-1, Que2-2; Que3 Member: Que3-1, Que3-2, Que3-3. Combining with petrology and well logging methods, the sedimentary subfacies can be further divided into alluvial diluvial sediments—channel sediments—floodplain—saline lagoons—desalting lagoons—pre- delta—delta front—pre- delta subfacies.Conclusions: The infrared spectral reflection technology can be used to accurately identify mineral types and obtain their relative content information. This technology has significant advantages in large- scale core scanning and fine stratigraphic division, which can provide scientific basis for the subsequent research on sedimentary system of regional geology.