To provide porous monodispersed particles obtained by preparing, as seed particles, poly(methyl methacrylate) particles or acrylic resin particles comprising 70% by mass or more of methyl methacrylate as a copolymerization component, swelling the seed particles 20 to 80 times the size of the original seed particles by mass using a swelling solution comprising an oil-soluble polymerization initiator and a monomer mixture containing 70% by mass or more of methyl methacrylate and 3 to 8% by mass of divinylbenzene, and polymerizing the monomers. The particles are porous particles with a diameter of the order of micrometers and a narrow particle-size distribution and are monodispersed. Colored monodispersed particles obtained by agglomerating a pigment in the porous monodispersed particles are monodispersed and spherical, and contain a large amount of pigment therein.