Polylactide (PLA)/halloysite nanotube (HNT) nanocomposites with different HNT contents were prepared by melt compounding. The morphology, crystallization behavior, as well as thermal and mechanical properties of the nanocomposites were studied. The results showed that HNT were well dispersed in PLA matrix. Thermogravimetric analysis data revealed that the thermal stability of PLA was decreased with the increasing of HNT content. Differential scanning calorimetry analysis indicated that the presence of HNT could promote cold crystallization and lead to different crystalline phase formation. The flexural and tensile modulus of PLA/HNT nanocomposites improved significantly with the incorporation of HNT. Compared with neat PLA foam, PLA/HNT nanocomposite foams showed much higher cell density and smaller cell size due to HNT serving as the heterogeneous nucleating agents. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013