One of the unresolved issues in the evaluation of coalbed methane (CBM) reserves is whether the long-term production profile is exponential or hyperbolic. The type of decline used to forecast production can have a significant effect on the remaining reserves; hence, a thorough investigation of CBM decline is warranted. Before investigating the decline behaviour of CBM wells, the literature on conventional gas decline analysis is summarized and the factors affecting production performance are discussed. The production performance of CBM is then investigated and compared to conventional gas performance. Simulations were conducted in order to determine the sensitivity of the hyperbolic decline exponent, to different reservoir and operating conditions. Several parameters, including the flowing pressure, were found to affect the decline behaviour of CBM wells. Finally, it was determined that, in spite of the more complex production mechanisms, the decline behaviour of CBM is similar to that of conventional gas.