In semi-arid areas of north China, deficiency in soil available P is a serious problem. Information on soil P availability between nonmulched and mulched plastic film in spring wheat is very limited. Hence, the objectives of the present study were to: (1) investigate the effect of PFM on soil total P budget and balance, (2) evaluate P availability of spring wheat soil with PFM, and (3) characterize changes in inorganic P fractions and transformation on a calcareous soil with PFM.