A study was made of suspension copolymerization of ethylene glycol dimethacrylate (EDMA) with some hydrophilic monomers (M2) to prepare gel particles having a large number and various kind of functional groups on their surface. Delayed charge of M2 to partially prepolymerized EDMA suspension resulted in the formation of favorable particles. The polymerization leveled off despite an appreciable amount of remaining M2 in the aqueous phase, and the amount of copolymerized M2 and the fraction of on-surface M2 units depended significantly on the kind of M2 as well as the mode of M2 charge. These dependences were explained in terms of the partition coefficient of M2 between EDMA and water and the monomer reactivity ratio.