The project background of large inverted T-shaped dock gate in extremely cold area is introduced, its gate body structure is optimized, and the system design in equipment requirements and working conditions is conducted. The dock gate pipeline system, dock gate external anti-freezing system, dock gate internal water tank anti-icing system, dock gate internal dry tank heating system, and dock gate electronic control system can meet the operation requirements of extremely cold area, which can provide greater reference value for the design and development of similar equipments.