Provided is a slide fastener assembling device capable of mounting metallic stop sections to fastener chains to which first sliders and second sliders have been mounted. A slide fastener assembling device is provided with: a first gripper (20) for gripping and transferring a continuous fastener chain (C1); a cutting device (30) for cutting the continuous fastener chain (C1) into fastener chains (C2) having a predetermined length, the continuous fastener chain (C1) having been transferred by the first gripper (20); a second gripper (40) for receiving the fastener chains (C2) from the first gripper (20) and transferring the fastener chains (C2); a first slider mounting device (50A) and a second slider mounting device (50B), the first and second slider mounting devices (50A, 50B) mounting first sliders (S1) and second sliders (S2) to the fastener chains (C2) transferred by the second gripper (20); and a stop section mounting device (60) for mounting metallic or resinous stop sections (P2) to the fastener chains (C2) having been transferred by the second gripper (40).