Abstract: The round baler for ensiling of rice straw was studied.The combined baler with the system of spraying liquid additive is beneficial to improve its adaptability by experimental results, and can provide references for improving straw-havesting machinery in technology. By experimental study, the baler can adopt two sets of short belt and six steel rollers for baling room, and can install nozzles at the entrance of the baling room, which is convenient for conditioning of rice straw.