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The Manas mining area is the main enrichment region for coal seams of the Xishanyao formation on the southern margin of the Junggar Basin. This paper discusses the geologic conditions necessary for coalbed methane occurrence, gas accumulation, adsorbability, dual porosity, and permeability of coal reservoirs based on coal samples and field data from Wells MMC1 and MMC2. The endogenetic cracks are development in the major commercial seams of Manas. Pores in commercial seams are mainly micropores, and the porosity is approximately 7.10%. The results of low-temperature nitrogen adsorption showed that the BET specific surface area is 1.6276 m 2 /g on average. Coal reservoirs exhibit heterogeneity and low permeability despite overall good reservoir properties and interconnectivity. The Langmuir volume is large, which is favorable for coalbed methane adsorption. However, the Langmuir pressure is low, and the field coalbed gas content may reach 6.4 m 3 /t. Coal reservoir characteristics may be related to coal rank and maceral as well as mineral content. In general, coal reservoir properties are good in Manas, which is beneficial for coalbed methane accumulation and high yield.