The invention provides a novel electric shovel pushing and pressing main shaft nut fixing device and belongs to the technical field of electric shovel equipment. The novel electric shovel pushing and pressing main shaft nut fixing device mainly solves the problem that pushing and pressing main shaft locking keys in the prior art are prone to falling off. The novel electric shovel pushing and pressing main shaft nut fixing device comprises a pushing and pressing main shaft nut, a pushing and pressing main shaft, locking keys, nut key grooves formed in the end faces of the pushing and pressing main shaft nut, main shaft key grooves formed in the lateral walls of the pushing and pressing main shaft, and interlocking rings, wherein the locking keys are located in the nut key grooves and the main shaft key grooves, and each locking key is fixed in the corresponding nut key groove in the end face of the pushing and pressing main shaft nut through two fastening nuts. The novel electric shovel pushing and pressing main shaft nut fixing device is characterized by further comprising locking plate fixing devices; each locking plate fixing device is composed of a locking plate, locking plate bases and fastening bolts, wherein the locking plate bases are arranged on the two sides of the corresponding nut key groove, the locking plate is fixed to the locking plate bases through the two fastening bolts, the locking plate and the corresponding locking key are in a cross orthogonal state, and the two fastening bolts on each locking key and the two fastening bolts on the corresponding locking key are interlocked through the interlocking rings respectively.