AbstractIn this study, two local strains of Penicillium chrysogenum named EGEK458 and EGEK469 were selected for enhancement of Penicillin G (PenG) production under solid state fermentation (SSF) conditions. These two strains were selected among seven strains according to their fermentation yields for PenG production during previous tests under submerged fermentation conditions. Sugar beet pulp, an agro-industrial residue of the sugar industry, was used as an inert support for the first time in PenG production under SSF. In order to enhance the production of PenG, two points of moisture level and three concentration values of nutrients (impregnated in solid support), which are the key parameters in production of PenG, were compared. As the yields from solid and submerged fermentation were compared, 570U/g of PenG – almost 15 times higher quantities of its production vs. submerged conditions – were obtained under SSF conditions in 50 hours by the strain EGEK458. The conditions for the enhanced production of PenG were 65% moisture content with a four-fold concentrated nutrients impregnated solid support.