Steam reforming of oils produced from waste plastics such as polyolefins has been investigated with a view of producing hydrogen. Steam reforming of oils produced by decomposition of plastics at relatively low temperatures (350-450degreesC) was carried out at temperatures from 600 to 800degreesC using commercial Ni/Al2O3 catalysts. Gas yield, gas composition, carbon conversion and coking characteristics were examined. Oils from both polyethylene and polystyrene were well gasified with very high carbon conversions and low coking rates at temperatures higher than 700degreesC. The gas components were consistent with calculated equilibrium compositions. The coking rate of polystyrene oil was lower than that of polyethylene oil, and the coking rate was the lowest at the temperature of 800degreesC.