This paper reports the synthesis and magnetism of a new polymer-inorganic intercalation nanocomposite based on a C-60-Containing poly(ethylene oxide) (C-60-PEO) into layered MnPS3, which is characterized by XRD, IR and thermal analyses. The lattice expansion (Delta d) of the intercalation nanocomposite is about 9.3 angstrom indicating the successful intercalation. And the charge balance is maintained by K+ ions coordinating with PEO chain of C60-PEO polymer, which come from the pre-intercalation compound Mn1-xPS3[K-2x(H2O)(y)]. Magnetic measurements indicate that the intercalation nanocomposite (C-60-PEO/MnPS3) exhibits a magnetic phase transition from paramagnetism to ferrimagnetism at about 40 K. And the distinctive hysteresis of M-H relationship further confirms that it is a low temperature ferrimagnetic nanocomposite. (c) 2007 Elsevier Ltd. All rights reserved.