To enable waste straw to be shredded and discharged well regardless of the amount of the waste straw fed to a waste straw-shredding device.

The subject waste straw-treating structure has a waste straw-conveying device 4, an opening and closing body 16 and a rotary body 23. The waste straw-conveying device 4 receives the waste straw after threshing treatment in a horizontal posture from a feed chain 3 of a threshing device 1, and conveys the waste straw to a waste straw-receiving port 14 formed at the upper part of the waste straw-shredding device 5. The opening and closing body 16 can be switched by turning between an opened state for allowing the waste straw to be dropped and fed to the inside of the waste straw-shredding device 5 from the waste straw-conveying device 4 by opening the waste straw-receiving port 14, and a closed state for blocking the dropping and feeding of the waste straw to the inside of the waste straw-shredding device 5. The rotary body 23 is formed at the opposing face 20 to the waste straw-receiving port 14 in the opening and closing body 16 and is regulated so that, when the opening and closing body 16 is switched to the opening state, the rotary body 23 may become into a state in which the waste straw is raked from the waste straw-conveying device 4 into the waste straw-receiving port 14.