The invention relates to the technical field of intelligent environmental protection engineering construction, and particularly relates to a large deep foundation pit supporting construction structureand a method thereof. The large deep foundation pit supporting construction structure comprises a pavement, a side slope, a foundation pit side face, an upper soil nailing wall arranged on the surface of the side slope, a lower soil nailing wall arranged on the side face of a foundation pit, a crown beam, concrete supporting columns, concrete piles arranged on the pavement, steel pipes, a blocking net and steel wires. The method further comprises the steps of building the concrete piles, building the upper soil nailing wall, building the crown beam and the concrete supporting columns, building a blocking facility and building the lower soil nailing wall. The large deep foundation pit supporting construction structure and the method thereof solve the technical problems that in the prior art, in the deep foundation pit construction process, supporting is not firm, and the occupied area of a protection net is large.