The feature of dynamic response of different highway roadbed height under the action of seismic dynamic loading is analyzed by using numerical simulation. The distributions of amplification factor of peak acceleration, peak velocity, peak displacement and relative displacement are comprehensively analyzed under various heights. Some useful conclusions that the distributions of amplification factor of peak acceleration, peak velocity, peak displacement increase gradually with the raising of height is gone. Conclusively, thegrowth is low at the bottom part of slope, the top is fast. The contour is dispersal by slope shoulder point as circle center approximately, and increases gradually on the pavement from inner to outside. The contour of relative displacement is the similar to the amplification factor of peak displacement. It reaches the maximum at lateral slope mass of slope upper part. In general, it growths faster at the low 1/3 of slope mass, and changes a little at the upper part 2/3 of slope body. They have a more significant mutation between the two parts. The approximate position of instability slip surface under the seismic action is revealed. The change gradient is large at themiddle of roadbed, and is small at both sides. That is, the instability slip surface is easy to form at the middle of roadbed. The contour parallels to the foundation surface approximately and the distribution occur layers.