Karst carbonate reservoir development prediction draws much attention from petroleum geologists all over the world. Paleozoic karst carbonates is the most favorable for giant hydrocarbon pools exploration in the Tarim Basin, northwestern China. Based on karstification type and paleogeography evolution analyses, the paper investigates the karst development respondence to sea-level fluctuation taking the early Paleozoic Tarim Basin as an example. The analyses shows the penecontemporary karstification was developed during the regression stage in the Early Paleozoic Tarim Basin, which provides diagenetic fluid conduct layer for the subsequent buried and freshwater karstification. The seismic reflection profile shows there are two stages of freshwater karstification, which rebuilt upon the former penecontemporary karstification. Integrated research reveals that there was remarkable relationship between the karstification and the sea-level fluctuation in the Early Paleozoic Tarim Basin. The sea-level fluctuation was an important controlling factor for karst carbonate reservoir development in the Early Paleozoic Tarim Basin.