PURPOSE: To provide a bag-in-box sellout processor in which a control means can be made simple as much as possible, and can exact operation of the bag- in-box can be attained.

CONSTITUTION: Liquid storing chambers 17a and 17b are provided at positions lower than those of bag-in-boxes 1a and 1b, and when cocks 21a and 21b on gas releasing paths 20a and 20b are opened, gas remaining in the liquid storing chambers 17a and 17b is discharged from sirup outlet by sirup raw materials naturally dropping from the bag-in-boxes 1a and 1b.