The invention relates to a lubricating protection device for a linear guide rail of an injection molding machine. The device comprises a first installation support and a third installation support, wherein the first installation support is arranged on the linear guide rail of the injection molding machine in a sleeving mode, and the third installation support is fixedly installed on slide feet ofa movable template of the injection molding machine, an oil way block is installed on the third installation support in a sliding mode, a second installation support is fixedly installed on the firstinstallation support, and the second installation support is fixedly provided with an oil way rolling wheel. According to the device, when the linear guide rail of the injection molding machine moves,the lubricating protection device moves, the guide rail surface of the linear guide rail of the injection molding machine is coated with grease through the oil way block, the upper part of the guiderail is coated with the grease through the oil way rolling wheel, so that working surfaces of the linear guide rail of the injection molding machine are prevented from rusting, the service life of thelinear guide rail of the injection molding machine is prolonged, and the precision of the linear guide rail of the injection molding machine is guaranteed.