Des-A-triterpenoids, diagenetic products of pentacyclic triterpenoids from A-ring degradation, have great potential for tracking specific biological sources in the environment. Although des-A-triterpenoids with lupane, oleanane, arborane, and ursane carbon skeleton structures were presumed to be indicative of terrestrial vascular angiosperms, recent studies have also identified other sources of des-A-triterpenoids in lakes and peatlands, such as algae and aerobic bacteria. Therefore, des-A-triterpenoids are valuable in paleoclimatic and paleoenvironmental reconstructions from the perspectives of specific sources and microbial activities. des-A-triterpenoids could be more useful for source identification than n-alkanes and n-fatty acids, considering that n-alkanes and n-fatty acids have multiple and complex sources. In recent decades, des-A-triterpenoids have been successfully applied in paleoenvironmental reconstructions of lakes from East Africa, South America, and Europe. In China, des-A-triterpenoids have been observed and identified in petroleum, coal, and recent peatland deposits, but no des-A-triterpenoids have been detected in modern lake environments. Therefore, we systematically reviewed the configuration structures, biosynthetic pathways, biological sources, and paleoenvironmental applications of des-A-triterpenoids in lake environments. This review describes a practical methodology for identifying des-A-triterpenoids. In addition, we reported the occurrence of des-A-triterpenoids with different configuration structures and distribution patterns in lakes Wuliangsu and Poyang. For instance, di-unsaturated des-A-triterpenes with oleanane configurations were observed in eight of 21 surface sediments from Lake Wuliangsu. Alternatively, des-A-lupane and mono-unsaturated des-A-triterpenes with oleanane and ursane configurations were observed in samples from a sedimentary core collected from Lake Poyang at a depth of about 3 m. Our findings demonstrate that des-A-triterpenoids have great potential in and challenge paleoenvironmental and biogeochemical reconstructions of Chinese lakes. At the end of the review, we propose further directions and breakthroughs for this research area, such as improving analyzing protocols and technology, identification of the exact biological sources under a specific geological background of lakes, disentanglement of the mechanism of triterpenoid degradation, and application of environmental reconstruction in des-A-triterpenoid research.