The invention provides high-strength low temperature hot rolling resistant channel steel for a forklift gantry and a preparation method for the channel steel. The channel steel for the forklift gantry comprises the following chemical compositions in percentage by weight: 0.15 to 0.20 percent of C, 0.30 to 0.45 percent of Si, 1.30 to 1.45 percent of Mn, less than or equal to 0.025 percent of P, less than or equal to 0.015 percent of S, 0.07 to 0.09 percent of V, and the balance of iron and inevitable trace impurities. The preparation method for the channel steel for the forklift gantry comprises the following steps: performing preliminary desulphurization of hot metal, and controlling the sulfur content in the desulphurized hot metal not to exceed 0.020 weight percent; smelting in a converter, wherein a top-bottom combined blowing converter is adopted for smelting, and in the smelting process of the converter, aluminum ferromanganese is adopted for deoxygenation, and the oxygen content in the hot metal is controlled to be less than 30ppm; performing low frequency (LF) refining, namely fully stirring and slugging to generate white slag or yellowish white slag in the refining process; performing continuous casting, wherein an integrated stopper ladle is used in the casting process and square billet full-protective casting is adopted; and rolling. The prepared channel steel has high yield strength which is 475MPa in average, can meet the performance requirements for the channel steel for the forklift gantry, and can be produced at low cost.