An investigation is presented of the potential forest-based bioenergy resources in Pennsylvania, under current conditions. Existing US Forest Service data on standing biomass are combined with regional analyses of wood energy use to estimate the sustainable annual yield for the state, taking into consideration operational constraints. These data are compared to current energy use patterns in the state to provide a sense of the magnitude of the current availability of woody biomass as an energy feedstock. Results indicate that the total biologically-sustainable yield of woody biomass are currently no greater than 8 million dry tons per year, with approximately 32% of that coming from timber harvest residues. This amount corresponds to slightly more than 3% of the state's current rate of energy use. Currently, about 29% of this potential is being utilized.