PVA, starch and plasticizers were blended in Hake Rheometer to prepare the thermoplastic starch/ PVA blends. Two kinds of PVA (PVA1799 and PVA1788) and two kinds of starch( com starch and cassava starch) were used to plastify the blends. The plasticizing effects of 3 kinds of plasticizers( glycol, glycerol and acetamide) were studied. Results showed that PVA and starch could be thermoplasticly processed with appropriate plasticizer,PVA and starch. Acetamide could form strong hydrogenolysis with PVA and starch, resulting in better plastification on the blends. The PVA/starch blends were well plastified by acetamide and maintained favorable mechanical properties.