Porous butyl methacrylate/octadecyl acrylate (BMA/OA) copolymers were first synthesized by suspended emulsion polymerization and evaluated for oil absorbency application. Effects of initiator, cross-linking agent, precipitator, dispersant agent, and emulsifier, water/oil ratio on oil absorbency of BMA/OA copolymers were studied in detail. The maximum oil absorbency to toluene was 23.5g/g.