Starch, soybean residue, and four different organically modified montmorillonite ( I. 28E,I. 30P,I. 34TCN, I. 44P) were used to produced foams by melt-intercalation, using a twin-screw extruder. The microstructure, expansion rate, apparent density, water absorption rate, and compressive strength of the material were investigated. The results indicated that overall performance of the composite foams is influenced dramatically by the addition of different organoclay; the I. 34TCN achieves the least cell size, highest cell population, best uniform dispersion and, the largest expansion ratio, least apparent density, lowest water absorption rate and highest compressive strength; among the four composite foams, the overall performance of the material by adding I. 34TCN is the best.