The microemulsion system comprising water, methyl methacrylate, a-hydroxyethyl methacrylate, and n-dodecyltrimethylammonium bromide was polymerized and cross-linked with ethylene glycol dimethacrylate. Fast polymerization of the microemulsions to form solid polymers could be easily obtained using dibenzyl ketone as a photoinitiator. Morphology of the resulting polymeric materials formed from bicontinuous microemulsions indicates the existence of open-cell type microporous structures as determined by thermogravimetric analysis. Their pore sizes, as revealed by field emission electron microscope, decreased on increasing the surfactant concentration. This study provides the first simple method for varying the pore size of polymeric materials by microemulsion polymerization of a suitable system using different surfactant concentrations.