1. College of Earth Science，Northeast Petroleum University，Daqing 163318，Heilongjiang，China; 2. Chongqing Institute of Geology and Mineral Resources，Chongqing 404100，China

To make a more accurate analysis and prediction of volcanic reservoirs of Huoshiling Formation in Wangfu fault depression，the rock types，diagenesis，and its significance to volcanic reservoirs are studied based on cores，thin sections，and casting thin sections． The result shows that rocks of Huoshiling Formation in Wangfu fault depression can be divided into volcanic lavas，pyroclastic lavas，pyroclastic rocks，and sedimentary volcaniclasitc rocks，of which volcanic lavas are dominant． Volcanic rocks of Huoshiling Formation have mainly experienced ten types of diagenesis during the early and late diagenetic stages，among which weathering-leaching，tectonism，metasomatic alteration，filling，and dissolution are more common． It is found that the escape of volatiles，condensation，weathering-leaching，tectonism，and dissolution play a constructive role in the formation and evolution of volcanic reservoirs，especially，the diagenesis of weathering-leaching and dissolution． Whereas，cementation，compaction，and filling reduce the physical properties of reservoirs． Moreover，the process of filling is multi-stage and is the most destructive diagenesis．