Infrared　(IR)　spectrum,　X-ray　diffraction　(XRD)　and　transmission　electron　microscope　(TEM)　were　used　to　study　and　characterize　the　coordination　mechanisms,　products　and　morphology　of　organic　carboxylic　acid　during　homogeneous　precipitation　in　the　system　of　Ce(NO3)(2)center　dot　6H(2)O　and　urea　solution.　The　results　showed　that　monocarboxylic　acid　stearic　acid　played　a　role　of　surfactant,　and　the　product　was　still　orthorhombic　Ce2O(CO3)(2)center　dot　H2O　with　a　high　crystallization　degree.　In　turn,　duality-carboxylic　acid　tartaric　acid　and　tri-carboxylic　acid　citric　acid　were　combined　with　Ce3+　to　form　chelate　citric　acid　and　cerium　tartaric　acid,　respectively.　The　results　were　caused　by　different　mechanisms　of　reaction　in　the　solution.