Abstract: The hot melt adhesive with a high temperature resistance for steel?plastic composite pipe were prepared by reactive extrusion of PP melt?grafted with maleic anhydride. The effects of initiator, grafted monomer and elastomer concentration on the hot melt adhesive were investigated. The result indicated that the comprehensive performance of the resultant hot melt adhesive was excellent, and its peel strength and tensile elastic recovery rate reached 131.4 N/25 mm and 65.5 % respectively. According to the results obtained from the T?cycling resistance test in the temperature range of -40~130 °C, the peel strength of 122.2 N/25 mm could still maintained after 800 times of circulation, and the loss ratio of peel strength rate was kept at just 7.0 %, which was evidently lower than the other two commercial hot melt adhesive.