Examining seismogram envelopes of regional earthquakes in Central Asia with focal depths deeper than 150 km in 1s--20s periods for a wide lapse time range up to 2000s, we found an offset in each coda envelope before and after the ScS arrival at 10s and 15s periods. The ScS wave has its own tail, that is, scattered waves of ScS waves sometimes dominate over the original coda waves composed of scattered S waves and scattered surface waves. For 1s, 2s and 4s periods, such an offset is not clear. However, there is a change of coda decay gradient associated with the ScS arrival. In a layered velocity and attenuation structure according to the PREM, scattering process of S-waves can be simulated by using the Monte Carlo method based on the radiative transfer theory for isotropic scattering process. Comparing numerical simulation for a two-layered scattering model with observed envelopes, we estimated the total scattering coefficients as 1.129 ¿ 10-3 km-1 and 6.230 ¿ 10-4 km-1 at 4s, and 4.510 ¿ 10-4 km-1 and 2.710 ¿ 10-4 km-1 at 10s, for the lithosphere and upper mantle and for the lower mantle, respectively. In the lower mantle, scattering loss is dominant in the total attenuation of S waves.