In this study, microfluidics integrated with sol–gel processes are introduced in preparing monodisperse ceramic nuclear fuel microspheres using nonactive cerium as a surrogate for plutonium. Detailed information about microfluidic devices and sol–gel processes used in the research is also provided. The effects of the viscosity and flow rate of the continuous and dispersed phase on the size and size distribution of CeO2microspheres were investigated. A comprehensive characterization of the CeO2microspheres has been conducted, including the X-ray diffraction pattern, scanning electron microscopy, density, size, and size distribution. The size of prepared monodisperse particles can be controlled precisely in the range of tens of micrometers to a millimeter and the coefficient of variation of the size distribution is below 3%.