The invention discloses low-temperature-resistant high-impact-toughness wind electricity steel and a producing method thereof. The wind electricity steel comprises, by mass, 0.30-0.38% of C, 0.20-0.35% of Si, 0.55-0.80% of Mn, 0.85-1.15% of Cr, 0.15-0.25% of Mo, 0.10-0.20% of Ni, 0.020-0.040% of Al, no more than 0.018% of P, no more than 0.008% of S, 0.0040-0.0080% of N, the balance Fe and inevitable impurities. The producing method comprises the following procedures of smelting, continuous casting, heating, rolling and thermal refining. According to the low-temperature-resistant high-impact-toughness wind electricity steel and the producing method thereof, through the compound action of Al and Ni, the low-temperature resistant high-impact toughness of common CrMo steel in alpine-cold region is remarkably improved, low temperature performance requirements of the wind electricity steel are met, and the impact Akv2 of the wind electricity steel at -40 DEG C is equal to or greater than 75 J.