As a complex sandstone reservoir affected by igneous rocks, the Eocene sandstone reservoirs in BZ oilfield are featured by complex geological characteristics and unclear genetic mechanisms, posing great challenges to the internal adjustment and tapping of the oilfield. Core data, logging data and production dynamic data were integrated to identify high permeability zones. By analyzing the parent rock type, acid fluid, fractures and mud content, the main controlling factors of high-quality reservoir were defined, and the reservoir evolution model under different geological conditions was clarified. The analysis results show that sufficient acidic fluid and feldspar-rich sandstone in BZ oilfield are the basis for large-scale dissolution, providing favorable material conditions for large-scale dissolution under medium-deep layers. The widely developed fractures are of great significance for the formation of secondary dissolution pores and the improvement of pore connectivity. The mud content has a triple superposition effect on reservoir evolution, resulting in a sensitive effect of mud content on the current pore evolution and differential distribution characteristics of reservoirs. Based on the genetic analysis and identification of high permeability reservoir, the spatial distribution pattern of high permeability reservoirs in the BZ oilfield has been clarified. The research results have guiding significance for the internal development adjustment and potential tapping of BZ oilfield, and have guiding significance for reservoir evaluation and production capacity prediction of other medium-deep oilfields in the Huanghekou Depression.