Combination of an open and a hidden excavation for constructing a vertical orthogonal top exhausting air duct structure of a deeply-buried subway station is provided. Four horizontal air ducts: left and right piston air ducts, an exhaust air duct, and a fresh air duct are thrown out of the underground, respectively, leading to left and right piston air shafts, an exhaust air shaft, a fresh air shaft, and an entrance/exit of fire-fighting. The fourth underground floor is communicated with the hall floor of the station main body, and the fifth underground floor is communicated with the running tunnel and the platform floor of the station main body. During operation, the train will enter and exit the station through the fifth underground floor of the air duct, and the piston air and heat will enter the four transverse air ducts through the air duct main body.