The invention discloses a turbocharger middle housing error proofing tool with a protector. The turbocharger middle housing error proofing tool with the protector comprises a cylinder body. An up-and-down height of a sliding sheet is greater than an up-and-down height of a clamping groove. An upward pressing plate is connected to an upper end point of a support. The upper end of the pressing plateis connected to an antiskid plate, the upper end of which is inclined toward the right side. The pressing plate and a sliding plate are connected through the torsion spring. During the usage of the turbocharger middle housing error proofing tool with the protector, the pressing plate is pressed downwardly, the pressing rod slides out of the clamping groove, the sliding plate can be moved up and down, the sliding plate can drive a guiding cylinder to move, the measurement blocks are moved upwardly to push open a cylinder cover and the pressing plate can be relieved when the measurement blocksarrives at a needed position, and then the pressing plate is shaken up and down, the pressing rod is clamped into a proximity clamping groove and then the measurement blocks can be taken out for usage. When the turbocharger middle housing error proofing tool with the protector is not in use, the measurement blocks are arranged inside the cylinder body, an upper cylinder cover is closed to preventthe measurement blocks from tear and wear. As a result, the measurement blocks cannot be impacted whether being moved or placed. The turbocharger middle housing error proofing tool with the protectorcan well protect the measurement blocks and thus can improve measurement accuracy and service life.