The dominantly distributed carbonate reef-beach facies reservoirs in Puguang Gas Field, the northeastern Sichuan Basin, are characterized by multifold lithofacies, diverse and complex reservoir space types, and strong heterogeneity, and the involved parameters are difficult to be described in either qualitative or quantitative way. On basis of this, reservoir space types are then identified by use of acoustic/density logging data in amplitude ratio and the reservoir characteristic parameters are thus classified. Finally, the storage capacity and distribution of reservoirs are presented by such parameters like the energy storage factor.