Very low-grade metamorphic rocks are widely spread in the sedimentary basin. During the diagenetic to low-grade metamorphic process, the evolution stage of petroleum and coal would undergo corresponding changes with the increasing metamorphic grade. Thus, the very low-grade metamorphism has close relationship with oil, gas, coal and other energy mineral resources. This paper first summarizes some aspects of this problem and the new progress in the study of very low-grade metamorphism, such as the dividing of very low-grade metapelitic zones, geothermobarometry on clay minerals, metamorphic p-T-t path and their application to the sedimentary basin, and then preliminarily discusses the Triassic very low-grade metamorphism in the Zoigê depression, northwest Sichuan. Studies show that the research on diagenetic to very low-grade metamorphism in the sedimentary basin has great theoretical and practical significance in dividing the boundary between diagenesis and metamorphism, determining the stage of basin maturity, recovering the paleotemperature and paleotectonic history and, on such a basis, guiding oil and gas exploration.