System and method for preventing external water from flowing into tunnel through cable duct bank

The invention discloses a system and method for preventing external water from flowing into a tunnel through a cable duct bank, the system comprises the cable duct bank and a cable tunnel, an isolation water-collecting well is arranged under the ground at the communication position of the cable duct bank and the cable tunnel, an isolation wall is arranged between the isolation water-collecting well and the cable tunnel, and the cable duct bank is communicated with the isolation water-collecting well. A cable duct bank hole is formed in the side wall of the isolation water-collecting well, the isolation water-collecting well is communicated with the cable tunnel through the cable hole, the bottom of the isolation water-collecting well is lower than the cable hole and the cable duct bank hole in the isolation wall, and a water pump and a liquid level switch are arranged at the bottom of the isolation water-collecting well; on the basis of the prior art, the isolation water-collecting well and the water pump are