Fungi are essential part of the ecosystem because they play an important role in the decomposition of organic materials such as plant residues. Fungi feed on dead organic matter and return the nutrients back into the soil. However, the occurrence of fungi growing on leaf litters which are responsible for decomposition are not yet fully studied and documented. Thus, in this study the different species of fungi present in leaf litters of three species of forest trees namely, rain tree (Samanea), orchid tree (Clitorea) and paper tree (Gmelina) were isolated and identified. These fungal species could be potentially used to hasten the decomposition of enormous leaf litters of forest trees. The isolated fungal species were screened for their ability to produce cellulase. A total of 30 species of phyllosphere fungi were isolated namely: