Based on the geological and logging data from 17 wells and the physical properties test results of 141 rock samples, this paper studied the characteristics and distribution of the Carboniferous volcanic reservoirs of different volcanic rock mass in the eastern Junggar Basin after analyzing the lithology、lihtofacies and capacity data. The results show that six volcanic lithology and two lihtofacies are recognized. The main lithology and lithofacies of XS3 rock mass are andesite, volcanic breccia and overflow facies apart, while that of XS6 rock mass are carbon mudstone, volcanic breccia, volcanic tuff and eruption facies respectively. In XS3 and XS6 rock mass, dissolution pore is the major reservoir space as well as gas pore and fracture are the minor ones. Physical properties are characterized by high porosity and low permeability while throats of pore are fine and poorly sorted. In fact, the overall physical properties of XS3 rock mass is better than that of XS6 rock mass. Effective reservoirs are affected by lithology, lithofacies and main faults. First, lithology determines the type of reservoir space and physical properties. Secondly, the lithofacies have an effect on the longitudinal distribution of the reservoir. Finally, the faults control the spatial distribution of the reservoirs and the developing degree of the secondary fractures. The effective reservoirs are concentrated close to the deep faults.