Carbonate cements are extensively developed in the Eocene sandstone reservoirs of JZ Oilfield, resulting in significant degradation of reservoir quality and connectivity. Some strongly-cemented tight layers even constitute seepage barriers for oil–water movement. Based on the comprehensive utilization of thin section analysis, cathodoluminescence, carbon and oxygen isotopes analysis, electron probes analysis, and well logging data, the types, origin, distribution, controlling factors and quantitative evaluation of carbonate cements were systematically studied. The results show that the tight layers in the study area are mainly composed of early bioclastic-rich carbonate, early basal ferric calcite, and middle-late pore-filling sparry calcite. The accumulation of bioclasts and the high evaporation of paleoclimate environment provided sufficient material sources for the formation of early carbonate cements, while the organic acids carried by oil and gas charging effectively inhibited the formation of middle and late carbonate cements. In order to describe the degree of carbonate cementation, four logging curves of GR, DEN, CN and RD were selected as input variables, and a prediction model containing 46 decision conditions was constructed by using decision tree algorithm to accurately characterize the varied carbonate cementation. The predicted results of this model are basically consistent with the carbonate content of rock debris logging, which can effectively evaluate the degree of carbonate cementation of Eocene sandstones.