Abstract: The existing methods for testing the construction quality of road base are expensive, in terms of both labour and time, though they are direct and reliable. As a result, they can only be applied on limited measuring points, and can hardly reflect the quality of the whole road base continuously. In order to solve this problem, the relationship between the tamping degrees and the elastic velocities of road base materials is studied in laboratory. The study result can provide the physical foundation for the test of road base construction quality using wave propagation method. It is psooible to carry out the continuous and overall test of road base construction quality by wave propagation method.