A composition for producing a glass fiber, including the following components with corresponding percentage amounts by weight: 54.2-64% SiO2, 11-18% Al2O3, 20-25.5% CaO, 0.3-3.9% MgO, 0.1-2% of Na2O+K2O, 0.1-1.5% TiO2, and 0.1-1% total iron oxides including ferrous oxide (calculated as FeO). The weight percentage ratio C1=FeO/(iron oxides−FeO) is greater than or equal to 0.53. The total content of the above components in the composition is greater than 97%. The invention also provides a glass fiber produced using the composition and a composite material including the glass fiber.