Rice straw (RS) polypropylene (PP) composites were prepared in the different ratios of 10:90, 20:80, 30:70, 40:60 and 50:50 (RS wt% : PP wt%) by extrusion moulding and hot press compression technique and investigated the mechanical properties like tensile strength (TS), bending strength (BS), impact strength (IS) and elongations at break (Eb%) of the composites. RS was soaked in the different ratios of urea solution and it was observed that 1% urea-treated RS content composites exhibited better mechanical properties. Gammairradiated RSPP composites showed superior performance. Water uptake and degradation studies of composites were also monitored.