The invention relates to oriented silicon steel and a preparing method thereof. The oriented silicon steel comprises, by weight, 0.030%-0.070% of C, 2.8%-3.5% of Si, 0.15%-0.30% of Mn, 0.35%-0.80% of Cu, 0.0040%-0.015% of S, 0.015%-0.025% of Als, 0.070%-0.015% of N, smaller than or equal to 0.020% of P, 0.002%-0.02% of Ti, and the balance Fe and inevitable impurities, wherein C / Ti is smaller than or equal to 10, and Cu / S is larger than or equal to 50. The preparing method comprises the steps of converter smelting, vacuum treatment, continuous casting, soaking pit heating, hot continuous rolling, first-time cold rolling, decarburization annealing, second-time cold rolling, MgO parting agent coating, high-temperature annealing and rewinding, the iron loss P1.7 of the oriented silicon steel is smaller than 1.18 W / kg, and the magnetic inductance B8 of the oriented silicon steel is larger than or equal to 1.86 T.