Starch /PVA composite foaming materials were prepared by the batch extrusion foaming processing. With fixed starch content and glycerol as plasticizer, the influences of the dosage of Azodicarbonamide (AC foaming agent) and Polyvinyl Alcohol (PVA) were studied on the apparent density, foaming ratio, relative hardness, water absorption rate, springback property and compression property of the foamed materials. The results indicated that with the increase in the content of PVA, the apparent density and the compression modulus of the composite foam material decreased, while the springback property of the material became better. The effect of PVA content on water absorption was not obvious, and the water absorption was stable at about 20%. When absorbing water to a stable state, the relative hardness increased with the increase of PVA content. With the increase in the content of AC foaming agent, the apparent density and relative hardness of the composite material decreased, the foaming ratio and the rebound rate increased, and the cell diameter gradually increased while the uniformity of cell diameter decreased. When the PVA content was 30% and the content of foaming agent was 1%, the material performance was the best.