The electron emission induced by highly charged ions 207Pbq+(24≤q≤36) interacting with Si(110) surface is reported. The result shows that the electron emission yield Y has a strong dependence on the projectile charge state q, incidence angle ψ and impact energy E. In fitting the experimental data we found a nearly 1/tanψ dependence of Y. Theoretical analysis shows that these processes are closely related to the process of potential electron emission based on the classical over_the_barrier model.