Different types of marine carbonate rocks have different capabilities of resisting diagenetic alteration and preserving coeval seawater information. The analyses of rock fabrics, cathodoluminescence and trace elements of Triassic marine samples of different rock types from the Huaying Mountains of eastern Sichuan Province were conducted in this paper to evaluate their capabilities for resisting diagenetic alteration and preserving coeval seawater information. In summary, the Triassic marine samples of different rock types from the Huaying Mountains of eastern Sichuan Province have different capabilities for resisting diagenetic alteration and preserving coeval seawater information.