A SCSI cable plug retaining seat includes two guide holes, two guide pins, and a seat. The two guide holes are combined to the upper and lower grooves of the cable plug. The two guide pins are installed to a channel unit connector. The seat has an L shape and the bottom thereof having an opening and has two screws and two screw holes. The retaining base of the present invention serves to fix the cable plug by the screw, and then is locked to the rear covering plate of the shelf. When the channel unit slides into the shelf through card guide, the channel unit connector will be guided into the guide holes by the guide pins so that the channel unit connector is precisely combined to the cable plug. Therefore, the connector can be pulled and inserted rapidly.