A seal-feeding station includes a seal receiver (21) for receiving a waterproof seal (20) fed through a seal feeding tube (16) and a seal keeper (23) for keeping the waterproof seal (20) transferred from the seal receiver (21) in an electric-wire insertion position. The seal receiver (21) includes a slider board (27) which is supported slidably between a standby position and a transfer position and includes an acceptance hole (27b) in which the waterproof seal (20) is fit in when the slider board (27) is in the standby position, and a push pin (38) which is movable forward and backward, is located so as to face the acceptance hole (27b) of the slider board (27) when the slider board (27) is in the transfer position, and moves forward to push the waterproof seal (20) fit in the acceptance hole (27b) and transfer the waterproof seal (20) to the seal keeper (23).