To provide a bundling adhesive tape cutter for easily installing a tape, capable of easily superposing and forming a nonadhesive part forming a picking part for easily separating an adhesive tape in the longitudinal direction by folding back the tape side edge.

This adhesive tape cutter has an inserting passage 34 of a bundling object W formed on a pair of support plates 12a and 12b, an extracting passage 36 for guiding the adhesive tape 2 extracted from a tape winding body 4 to the inserting passage 34, a rotational engaging member 40 rotated by allowing an engaging projection 40a to abut on the bundling object W moving in the inserting passage 34, a fastening member 42 to be sticked and locked with the adhesive tape 2 by abutting and sliding of the tip of the engaging projection 40a, an energizing means 44 for pressure contact for energizing the fastening member 42 toward the tip of the engaging projection, a tape cutting lever 50 having a cutter blade 54 for cutting the adhesive tape 2 in the inserting passage 34 under the fastening member by being push-rotated by the bundling object W moving in the inserting passage 34, and a superposing part forming means 60 arranged in the extracting passage.