The invention discloses a split type misoperation preventing device for secondary equipment of a transformer substation and a protection method implemented by the split type misoperation preventing device, and relates to the field of protection devices for equipment. The split type misoperation preventing device is characterized in that strip-shaped gaps are reserved on the side walls of a stretching device, one end of a shelter is fixedly wound on the stretching device via the strip-shaped gaps, the shelter can be stretched under the control of the stretching device, the other end of the shelter is fixedly adhered on a pulling pressure plate, an outward semicircular protrusion is arranged in the middle of the pulling pressure plate, a lock hole is formed in the protrusion, a misoperation preventing lock can be inserted into the lock hole, the lock hole can be locked by the misoperation preventing lock, and soft magnets are arranged at the upper end and the lower end of the pulling pressure plate and are used for fixing the pulling pressure plate onto the secondary equipment. The split type misoperation preventing device and the protection method have the advantages that problems of influence of secondary measures arrangement modes on the power supply reliability, time and labor wastage during work, insufficient firmness and low work efficiency of existing transformer substations can be solved; the split type misoperation preventing device and the protection method can be applied to the field of transformer substations.