The invention relates to steel for a linear guide rail. The steel is prepared from the following chemical components in percentage by weight: 0.40-0.70% of C, 0.15-0.40% of Si, 1.30-1.80% of Mn, 0.30-0.60% of Cr, 0.005-0.030% of S, less than or equal to 0.025% of P, less than or equal to 0.25% of Ni, less than or equal to 0.30% of Cu, less than or equal to 0.10% of Mo, less than or equal to 0.05%of Al, less than or equal to 0.0010% of Ca, less than or equal to 0.003% of Ti, less than or equal to 0.0010% of O, less than or equal to 0.04% of As, less than or equal to 0.03% of Sn, less than or equal to 0.005% of Sb, less than or equal to 0.002% of Pb, and the balance of Fe and inevitable impurities. After being subjected to
quenching and
tempering, the steel has yield strength higher than orequal to 785 MPa, tensile strength higher than or equal to 930 MPa,
ductility higher than or equal to 12%, and Charpy
impact work AKU higher than or equal to 50 J at the normal temperature. Non-metalimpurities meet the following relationship: A-series fine
system less than or equal to 1.5, A-series rough
system less than or equal to 1.0, B-series fine
system less than or equal to 1.5, B-series rough system less than or equal to 1.0, C-series fine system equal to 0, C-series rough system equal to 0, D-series fine system less than or equal to 1.0, D-series rough system less than or equal to 0.5, Ds-series less than or equal to 1.0. Main process comprises electric furnace or converter-external refining-VD or RH vacuum degassing-
continuous casting-
continuous rolling-stack cooling. By optimizing chemical components of a steel plate,
hardenability, strength and
wear resistance of the steel are remarkably improved.