Abstract: The fault?controlled karst?cave reservoir body of the Ordovician in Tahe oilfield is one of the typical fracture?vuggy reservoirs in Tahe field. It is characterized by great potential for remaining oil development and obvious waterflooding effect. However, if unreasonable water injection mode may cause rapid water channeling along the top side and water breakthrough, resulting in low waterflooding recovery efficiency and short stable production. This paper presents the reasonable water injection mode and injection?production parameters for it in view of the main controlling factors of such a reservoir body controlled by faults by using reservoir numerical simulation and field statistical methods, in order to provide helpful references for EOR of the similar reservoirs