This work was aimed to study the biodegradability of water-soluble polyvinyl alcohol (PVA) packaging film. Through the process of cultivation, screening, isolation and purification, the strain with highest biodegradation efficiency was obtained, and its degradation effect on PVA was studied. Meanwhile, the effect of additives in the components of PVA packaging film on its degradability was analyzed with the methods of controlling variables and orthogonal experiment. The Penicillium strain showed the strongest ability in the degradation of water-soluble PVA packaging film, and the contents of various additives in the polyvinyl alcohol (PVA) water soluble packaging film promoted PVA degradation at a certain concentration. The degradation effect was most obvious when the contents of glycerol, sodium dodecyl sulfate and Tween were1.7%, 1.2% and 1.4%, respectively.