The invention relates to a displacement meter protection support and a simply supported beam bending test device. The displacement meter protection support comprises a supporting frame and a steel plate arranged on the supporting frame. The supporting frame comprises two steel channel beams distributed in the transverse direction and at least two supporting rods fixedly arranged on each steel channel beam; the two steel channel beams extend in the longitudinal direction, the steel plate is fixedly arranged above the supporting rods, and a through hole allowing the displacement meter to penetrate through is formed in the middle of the steel plate. The invention further comprises the simply supported beam bending test device. The beneficial effects of the invention are that: in application,the displacement meter is mounted below the displacement meter protection support; the displacement meter protection support is fixed below a fatigue testing machine, a measuring rod of the displacement meter penetrates through the steel plate through the through hole in the steel plate and abuts against the simply supported beam for measurement; when the simply supported beam is broken, the measuring rod of the displacement meter retracts downwards, the simply supported beam hits the steel plate of the protection support, and therefore the displacement meter is prevented from being damaged, and the protection support and the bending test device are simple and practical.