The growth of fungi on the surface of metals has great influence on their structural integrity and failure. The possibility of some fungal species to grow on metal surfaces is determined by their secreted metabolites which aid their adaptation to new environmental and nourishment conditions. The aim of this study is to determine the influence of Penicillium chrysogenum on the morphological and corrosion behavior of mild steel using gravimetric and potentiodynamic techniques. Mild steel coupons were contaminated with the above-mentioned fungus in Petri dishes with nutrient medium imitating organic pollution. The gravimetric and electrochemical analysis results revealed that the corrosion rate (CR) and weight loss (∆W) of the mild steel increased with time. The cumulative corrosion rate (ƩCR) increased from 1.74mpy in the absence of P.chrysogenum to 7.58mpy in the presence of the fungus while the corrosion current density (Icorr) increased to 258.6μAcm2 from 187.9 μAcm2.