Abstract: ObjectiveTo promote the resource utilization of waste cathode ray tube (CRT) glass and improve the mechanical properties of mine grouting materials, the fiber prepared by CRT glass was used to dope and modify the grouting materials. MethodThe effects of length, dosage and curing time on the strength of CRT glass fiber were investigated through uniaxial compression tests, and the strengthening mechanism of CRT glass fiber was discussed combined with microscopic images. ResultThe results show that the uniaxial compressive strength and ductility of mine grouting materials are significantly improved by adding glass fiber. The growth rate of strength decreased with the increase of curing time, 0～3 d for the rapid growth period, after 3 d of curing gradually stable; The fiber length has a significant effect on the strength index, and the contribution value of cut fiber to the strength increase is the highest. With the increase of fiber content, the compressive strength and flexural strength increased first and then decreased, and the maximum strength was reached when the fiber content was 0.3%～0.4%. ConclusionThe bridge effect of fiber in cement mortar can inhibit the expansion of compression crack and buffer the failure of specimen. However, when the fiber content is too high or the length is too large, the entanglement, connection, aggregation and clumping will occur, which increases the porosity of the local area and weakens the strength and deformation properties of the grouting materials.