This study sets a specific focus to explore the effectiveness of encapsulation of white-rot fungi as a novel biological pretreatment strategy on biogas production in anaerobic digesters. For this purpose, Trametes versicolor culture was entrapped in Ca-alginate beads and used in a fungal pretreatment step prior to co-digestion of cow manure, food waste, and waste-activated sludge. The results revealed that pretreatment with encapsulated T. versicolor led to an enhancement of biomethane production in all digesters and contributed to an increase in methane yield up to 35%. The maximum methane yield was observed in the digesters co-treating food waste and waste-activated sludge, recorded as 519 mL CH4/g TVSused. On the other hand, much lower methane yield (ranged 161-174 mL CH4/g TVSused) was observed in the digesters operated without food waste and the pretreatment did not reveal any considerable enhancement in methane production in these digesters.