The role of deep thermal fluid activity in the formation of sedimentary reservoir cannot be ignored. The deep thermal fluids discussed in this paper are non-hydrocarbon thermal fluids below the basin basement, including deep crustal thermal fluids and upper mantle thermal fluids. The identification markers of deep thermal fluid activity, methods and its effect on reservoir transformation were reviewed, and the research hotspots and development trend of deep thermal fluid-diagenetic response of glutenite reservoirs in clastic reservoirs are discussed in this paper. At present, the identification markers of deep thermal fluid activity generally include: ① rock and mineralogy characteristics; ② paleo-temperature characteristics; and ③ geochemical characteristics. Due to the effects of temperature and material composition, the deep thermal fluid emplacement can transform the sedimentary reservoir. The constructive and/or destructive transformation may coexist or alternate with changes in region, depth and time. The superimposition of deep thermal fluid and primary fluid on clastic rocks, especially glutenite reservoirs, and (ultra-) deep reservoir formation mechanism under the influence of deep thermal fluid are not only good supplements and enrichment for the study of fluid-diagenesis interaction, but also important frontier subjects of sedimentary geology in the world at present.