Uniform rice-like CdS particles were synthesized in cyclohexane/Triton X-100/n-pentanol/water quaternary microemulsions. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy, and electron diffraction. The results indicate that the size and the shape of the rice-like CdS particles can be influenced by the molar ratio of water to the surfactant（w value） and the reactant concentrations.
