To provide a work attitude changing device in a strapping machine which can easily change the attitude of a product when strapping the cylindrical product such as a car tire with a band.

The work attitude changing device in the strapping machine ties a substantially cylindrical tire 30 in the radial direction through a center hole. A side surface of a packing machine body 16 is formed to be a positioned surface, two supporting guide bars 20 and 22 are turnably fitted to the positioning surface in a substantially horizontal direction, and a band traveling passage 26 is disposed below the supporting guide bars 20 and 22 substantially parallel to the supporting guide bars 20 and 22. The tire 30 is supported astride the two supporting guide bars 20 and 22, and the tire 30 is turned by turning the supporting guide bars 20 and 22.