Abstract: A method of using biological processes as a pretreatment step in combined biological and mechanical paper pulping process is described. The process uses a species of fungus, Ceriporiopsis subvermispora, which has not previously been used for this purpose. It has been found that even with a non-optimized system, and with the stationary holding of the wood chips during fungal incubation, that significant savings in energy usage in the pulping process can be achieved compared to conventional mechanical pulping while simultaneously achieving increased strength characteristics in the paper.