The invention discloses a gauge protection device for geological drilling. The gauge protection device comprises a drill bit body and a plurality of gauge protection units which are arranged in the circumferential direction of the drill bit body. Each gauge protection unit comprises a first gauge protection tooth, a second gauge protection tooth and a push rod, wherein the push rod is located in the drill bit body, one end of the first gauge protection tooth and one end of the second gauge protection tooth are both exposed, the other end of the first gauge protection tooth and the other end of the second gauge protection tooth both stretch into the drill bit body, the portion, stretching into the drill bit body, of the first gauge protection tooth and the portion, stretching into the drill bit body, of the second gauge protection tooth are both hinged to the push rod, and the push rod is hinged to the drill bit body. By utilizing the gauge protection device, the service life of the gauge protection units can be prolonged, the frequency of replacement, caused by excessive abrasion of the gauge protection teeth on the drill bit body, of the drill bit body is decreased, the drilling efficiency is improved, and the drilling cost is reduced.