Abstract: Hotspot is a window to understand mantle plume hypothesis and dynamics of mantle plume, and the area where ridge interactions with hotspot is the best place to directly find out relationship between plate tectonics and mantle plume. Based on affirming mantle plume hypothesis, the authors introduce several 2D or 3D simulation experiments about ridge-plume (hotspot) interaction and some examples of hotspot-ridge interactions existing in the three oceans. It is further pointed out that simulation experiments combined with geology, petrology, geochemistry and geophysics(especially for high resolution seismic technique) in studying mantle(hotspot)-ridge interaction will play an important role in such reseaches as plume-ridge interactions.