Although lined tunnels usually pass through the alluvial valley; the study of their seismic responses is limited. The SH-plane wave scattering induced by an elastic-half-space lined tunnel in alluvial valley is studied with MATLAB program and the indirect-integral boundary element method. The influences of frequency

tunnel depth and incident angle are investigated on the surface displacement and the dynamic stress concentration factor of the internal and surface displacements of alluvial valley. The difference between tunnel and semi-space tunnel in alluvial valley is compared. The results show that the dynamic stress concentration of lined tunnel in alluvial soft clay is significant

and due to the high frequency incident waves

the effect of tunnel depth in alluvial area on the displacement distribution and lined stress spectrum as well as surface displacement is also significant.