Due to the high-cost and non-renewable materials for producing polyurethane foam, the lignin of rice as raw material, partially substituting phenol, was to synthetize lignin polyurethane foam. Firstly, the lignin was extracted from rice through ethyl alcohol. Then, the lignin was modified by epoxy chloropropane to increase the number of hydroxyl groups. The modified lignin was readily soluble in the polyether polyol, and could replace part of polyether polyol to mix with isocyanate and other additives developing resource-efficient polyurethane foam. This study not only provides the feasible solution of producing lignin polyurethane foam, but also makes effective use of agricultural waste.