The Loess Plateau is seated on the upper and middle stream of the Yellow River in northern China, covering an area of 440 000 km², with loess deposit thickness ranging from several meters to more than 500 meters. The Loess Plateau is one of the most tectonically active areas of the world and one of the most seismically active regions. More than 1.4 million people have been killed by the earthquakes in the region. The Wenchuan M_S8.0 earthquake in 2008 collapsed or seriously damaged enormous buildings, houses, and infrastructure. The field investigations, observations, and analyses indicate that a large number of casualties and tremendous economic losses were caused not only by the collapse and damage of houses with poor seismic performance, but also by the amplification effects of site conditions, topography, and the thickness of loess deposits on ground motion. The morphological characteristics of slopes determine the predominant frequency, which may amplify the incident seismic wave with the same or similar frequency range, and thus, increase the slope dynamic response and even trigger landslides. The field investigations of the Wenchuan earthquake indicate that the amplification effects of site conditions and topography on ground motion were very obvious in loess regions. In this paper, we chose a typical loess site for temporary strong motion array and numerical analysis, and aim to explore the dynamic response characteristics of the loess slope. The results reveal the following:(1) The minimum predominant frequency occurred at the slope crest. The highest peak ground acceleration (PGA) amplification coefficient reached 1.98 at the slope crest. The phenomenon of the low predominant frequency corresponding to the high PGA amplification at the slope top may be related to the ratio of slope height to the wavelength of incident wave. The PGA amplification was maximum when the ratio was 0.2. (2) The amplification effects are more predominant with increase in slope gradient. The predominant period amplification coefficient of response spectrum at the slope top may reach 5. The numerical results are basically consistent with the ground motion observations, and thus, they have high scientific and practical significances for engineering seismic fortification in loess regions.