Abstract: The action of holocene tectonic stress field on the Tangshan earthquake area left a series of physical traces,such as groud joints,trench network systems,drainage patterns,crust deformation and earthquake rupture zone,etc. These evidences prove that there have been at least twice deflections of the regional stress field towards the ENE and EN in this area since the Holocen epoch. It was just during the action of the tectonic stress field along the ENE that the great,Tangshan earthquake of 1976 took place.