PURPOSE: To provide a compact unit for opening a bag and processing an empty bag which can consistently and rapidly perform a task from opened bag discharging to compressionbagging of an empty bag of a bag body to contribute to environmental maintenance.

CONSTITUTION: A positioning device 74 for a bag body B, an opened bag discharging device 76 and an empty bag compression-bagging device 20 are adjacently placed inside a frame body 72. A guide rail 112 is horizontally provided above these three devices, wherein a moving body 114 is slidably engaged with the guide rail 112. A vertical cylinder 120 is provided on the moving body 114, and a vacuum cup 80 is attached to the lower end of a rod 122 of the vertical cylinder 120. The bag body B is moved by the vacuum cup 80 from the positioning device 74 to the opened bag discharging device 76 to have the opened bag discharged, and the empty bag B' is moved to the empty bag compression- bagging device 20 where compression-bagging is done.