Accurate models of the distribution of the elastic properties and density in the Earth’s mantle are important in wide areas of geophysics,geochemistry,and astronomy.The purpose of this paper is to describe the recent three-dimensional seismic model and geodynamics of the Earth’s mantle,especially been presented in IUGG XXI Assembly in Boulder,Colorado,USA in July 1995.The three-dimensional seismic models are constructed mainly by the data of broadband digital seismic networks.The velocity anomalies at different depths in mantle are characterized as follows.At a depth of 100km they follow the plate tectonic signature at surface.At a depth of 350km the principal expression of lateral variations are the differences between the continents and oceans.A ring of high velocities surrounding the Pacific basin.The topography on three internal mantle discontinuities(410km,660km,Core-Mantle Boundary)is shown.Two super-upwelling of mantle flow appear in south Pacific and west Africa in the lower mantle.The super downwelling plume underneath Asia is the dominant pattern of vertical mantle flow in the modern Earth.The mantle convection patterns in the upper mantle tend to be strongly controlled by the upwelling and downwelling superplumes in the lower mantle.The central Asia,from Indian subcontinent to Tibet,Xijiang,Mongolia and Baikal regions tend to be swallowed into the cold superplume forming the present largest collision and amalgamation places in the world.