A simple processing technique to produce novel magnetic poly(styrene-divinylbenzene) (Poly(St-DVB)) monoliths with highly open porous structure and lipophilicity is described. A porosity of 98.1% was achieved with the technique of high internal phase emulsions (HIPEs). The porous monolith possessed hydrophobicity with a water contact angle of 142 degrees and absorbed oils from water selectively with an oil intake capacity of approximately 23 times its own mass. Incorporation of carbonyl iron powders (CIPs) enabled magnetism allowing the oil-soaked composite to be readily collected by a magnet. The composite saturated with oils could be regenerated by simple centrifugation, and the tests showed that the oil intake capacities were not impaired after 10 absorption/regeneration cycles. As Poly(St-DVB) is a low-cost traditional material and is easily manufactured in monolithic forms via direct molding and controlled polymerization, the added features make the porous Poly(St-DVB) composite a very competitive candidate for oil/water separation.