Starch/EVA　(ethylene-vinyl　acetate　copolymer)/modified　kaolin　nanocomposite　foaming　materials　were　prepared.　The　modified　kaolin　was　obtained　by　g-methylacryloyl　oxypropyl　trimethoxysilane　(silane　coupling　agent　KH-570)　as　the　nucleating　agent.　The　effects　of　the　modified　kaolin　were　analyzed　by　activation　index,　and　the　structure　was　characterized　by　Fourier　transform　infrared　(FTIR)　and　SEM.　The　effects　ofmodified　kaolin　on　themechanical　properties　and　the　cellular　structure　of　the　composite　foams　were　also　studied.　According　to　the　results,　when　1.8　phr　(parts　per　hundert　parts　of　resin)　silane　coupling　agent　KH-570　modified　kaolin,　the　activation　index　was　100%.　It　was　found　that　the　modified　kaolin　played　an　important　role　in　the　formation　of　the　microstructure　and　themechanical　properties　of　the　composites　foams.Modified　kaolin　could　increase　the　amount　of　the　cells　and　reduce　cell　size　significantly.　The　optimum　tearing　strength　of　the　composite　foams　was　12.78　kg/cm　with　20　phrmodified　kaolin　added.　The　results　were　attributed　to　the　nucleation　effect　of　the　modified　kaolin　particles,　the　high　melt　viscosity　and　the　complex　interface　interactions　between　EVA　chains　and　kaolin　particles.　©　2013　WILEY-VCH　Verlag　GmbH　&　Co.　KGaA,　Weinheim.