In the loess region, the geotechnical disasters caused by the earthquake are serious. Taking a loess slope in the new Lanzhou area as a prototype, we conducted a large-scale oscillating table model test to study the dynamic response law and the loess slope failure mechanism under the earthquake load. The results showed that the acceleration amplification effect on the loess slope surface is obvious and reaches its maximum value on the slope shoulder. Meanwhile, the amplification effect increases with increasing seismic intensity, when the intensity reaches 600 gal, the maximum amplification coefficient on the slope shoulder is 2.06. The result also showed that ground pressure on the slope surface is less than the pressure on the slope body at the same elevation. The maximum value appeared on the slope of the free face and the value varies between 0.7-0.75 kPa. As the seismic intensity increases, the slope's superficial fissure gradually changes from a small short to a deep fissure, especially near the shoulder of the slope. In the test, the maximum settlement is about 10 cm and the maximum horizontal displacement of the slope shoulder is about 5-8 cm. The final failure mode of the model slope is traction break-slip. The research results may provide some reference for studying the stability of the loess slope under earthquake loads.