Abstract: In order to find out the effect of different combinations of bacteria pretreatment on biomethane conversion from lignite, phanerochaete chrysosporium, pseudomonas and streptomyces viridosporus were selected to carry out biological pretreatment and biogas production experiments of lignite. The biogas production detection and Gompertz equation simulation method, the effects of different combination strains pretreatment on lignite biogas production were discussed. The results showed that the biogas production of lignite increased significantly after microbial pretreatment, with the maximum increase of 127%. According to the results of different pretreatment sequence of the same strain, the pretreatment sequence of streptomyces viridosporus + pseudomonas and pseudomonas + phanerochaete chrysosporium was better. Compared with the pretreatment results of the same strain before that of other strains, the pretreatment sequence of pseudomonas + phanerochaete chrysosporium was better than that of pseudomonas + streptomyces viridosporus. The Gompertz equation for gas production fitting, it can be seen that coal samples pretreated by different strains have greater maximum methane yield and cumulative gas production potential.