The invention discloses a transposition buffer unit of electromagnetic valve cover machining equipment. The transposition buffer unit of the electromagnetic valve cover machining equipment comprises a transposition connecting plate; two longitudinal parallel transposition fixed frames are mounted on the upper end surface of the transposition connecting plate; longitudinal parallel first transposition linear guide rails are mounted on the upper end surfaces of the two transposition fixed frames; transposition buffer modules are respectively mounted on the transposition fixed frames on the outer sides of the two first transposition linear guide rails; V-shaped sections are arranged at the front ends of the two transposition fixed frames and the first transposition linear guide rails; limiting blocks are symmetrically arranged at the front ends of the two transposition fixed frames; positioning connecting plates are mounted on slide blocks of the two first transposition linear guide rails; handles are mounted on one sides of the positioning connecting plates; and dustproof plates are mounted on the edges of the positioning connecting plates. Through the mode, the transposition buffer unit of the electromagnetic valve cover machining equipment can accurately position and clamp a valve cover to improve the working efficiency and the machining precision.