A method for the production of biogas which uses a mixture of specific rumen fungi is disclosed. The method shall improve biomethane production and biogas potential of anaerobic digestion.Four isolated species of anaerobic rumen fungi of Orpinomyces sp., Piromyces sp. and Anaeromyces sp., Neocallimastix frontalis were selected and these species were mixed. After that, mixture of rumen fungi containing 4 species was added in the anaerobic digesters fed with animal manure at different inoculums ratios: 5% (R1), 15% (R2), 20% (R3) (v/v).