To achieve a multiply connected plastic ampule separating device of a batch separating system using a simple mechanism.

Multiply connected plastic ampules (10) successively supplied from an alignment, storage and successive supply part 30 and mounted on a transverse mounting part 70 in a transverse state are extruded in an ampule axial direction by an axial direction extrusion mechanism 80. Also, cutter blades 55 are lined on a cutter 54 of a separating part 50, an ampule fluctuation suppression mechanism incorporated in the separating part 50 is provided with a deformation prevention roller 52 to be in rolling contact with a thin connection part (12) between ampules in addition to a floating prevention roller 51 to be in rolling contact with an outer peripheral surface of each ampule (11), and the deformation prevention roller 52 is made to face the cutter 54. Further, the axial direction extrusion mechanism 80 is arranged below the alignment, storage and successive supply part 30, and a tilt control mechanism 40 for switching blockage/allowance of tile of the leading multiply connected plastic ampules (10) is constituted of a swing arm 42 whose swing center is positioned near the transverse mounting part 70 and a transverse bar member 41 supported at the swing end part and elevated and lowered.