Abstract: In Halahatang area of the Tarim Basin, the carbonate reservoirs, with maximum burial depth of over 7200 meters, are characterized by strong heterogeneity. Accordingly, it is difficult to identify and evaluate quantitatively the fractures and cavities. In this regard, a quantitative description technology for fracture-cavity carbonate reservoirs is adopted. Based on well-seismic data, beaded, flaky and chaotic seismic facies are established and their corresponding geometric structure models are built. Then, reservoir porosity model is built up with the constraint of well logging electrofacies reservoir model and seismic wave impedance. Finally, fracture-cavity space quantitative description, connectivity prediction and space description are completed. In virtue of this technology, fracture-cavity is described by quantification instead of the original attribute properties, so that prediction accuracy of heterogeneous carbonate reservoirs is obviously improved. The void leakage rate increases to 52.8% from 42%, and reservoir encountering rate increases to 91% from 82%. Obviously, this technology promotes effectively the exploration, development and production.