To improve the assembling work efficiency of a nearly triangular cylindrical container holder and make uniform the container holder itself.

This device is constituted of a magazine case 10 installed in a blank-supply station A to stock blanks 110, a means 20 installed in an adhesive-applying station B to apply an adhesive on tabs for sticking of the blanks 110, an assembling means 30 installed in an assembling station C to assemble a container holder 100 with a blank, and a transfer means 50 transferring the blanks 110 from the blank-supply station A to the adhesive-applying station B and the assembling station C in sequence and transferring the container holders 100 assembled in the assembling station C to the fitting station D. The blanks applied with an adhesive in advance on the tabs for sticking are bent by a bending structure of the assembling means 30 and thereafter, the blanks 110 are shaped to form a specified shape by a shaping and fixing structure 41 to fix the tabs for stiking applied with the adhesive at the specified position.