Abstract: The Ordovician pool of Tahe oilfield is of fracture-cave type and carbonatite pool with bottom water drive,and the pool is of extremely heterogeneous.Therefore,it is the key to make clear the distribution and the internal connectivity of reservoirs to improve the development effect.Comparison with production,water cut and fluid characteristic and other dynamic characteristics of Well S48 and Well T401 suggests that the two wells are extremely similar in change trend of dynamic performances,which shows that the two wells are connected,and the data of well interference tests validate the conclusion.It is convenient and expeditious to study the in- terwell communication by using the dynamic performance da- ta.