Abstract: The producing process of T91 seamless steel tube by CPE mill is introduced.Problems that may occur during the process are analyzed, and the quality of the produced Φ60 mm×7 mm T91 seamless steel tubes are evluated.The practical production shows that by adopting reasonalble heating schedule and reliable piercing parameters, and through elongating on the push-bench and the stretch reducing mill, a stable production of T91 seamless steel tube can be realized.For producing T91 seamless steel tube by CPE mill, the heating schedule and the piercing process shall be well controlled.