The Cluster spacecraft and ground-based Digisonde network observed on November 7, 2004 a strong interplanetary shock interaction with Earth's magnetosphere which initiated a strong magnetic storm with Dst = −373 nT. When the interplanetary shock encountered the Earth system, the Cluster fleet was traveling in the inner magnetosphere region (L shell = 4.2) at almost exactly the Cluster's perigee (around 0900 MLT). This event offers an excellent opportunity to study the geospace response to a powerful interplanetary shock. The angle between the sun-Earth line and the normal direction of the shock front is only 3.0 degree indicating that the shock hit the geospace at ∼12 LT initially. It is found that energetic particle fluxes are strongly enhanced and the shock related ionospheric phenomena have obvious longitudinal and latitudinal distribution. The interplanetary shock has a significant influence on the dayside mid-high latitude stations, e.g., Millstone Hill, Wallops Island, etc. whereas the stations in t...