Ultralong cerium-based coordination polymer (Ce-CP) nanobelts have been prepared from benzene-1,3-dicarboxylic acid (1,3-H₂BDC) and Ce(NO₃)₃via a facile solvothermal method, employing a cheap and non-toxic mixture of ethanol and water as solvent. The products were well characterized and analyzed. The nanobelts are dozens of micrometers in length, 50–200 nm in width, and 20–40 nm in thickness. Reaction parameters such as molar ratio of reactants, reaction temperature and time of preparation were also investigated in detail. CeO₂ nanobelts were obtained after calcining the CP nanobelts in air at 400 °C for 4 h. The activity of the catalytic reduction of p-nitrophenol by the 1 wt% Pt loaded CeO₂ nanobelts was investigated. Furthermore, other rare earth-based CP micro/nano structures were also prepared using this method.