In order to realize the guided wave energy to focus on the defects as soon as possible, a pipes ultrasonic guided wave defect detection method based on time reversal focusing theory was studied. Based on that, numerical simulation and experiments were carried out for steel pipe with different sizes of non-through-thickness defects. The reflection coefficient of the time reversal method is three times of that of the direct guided wave reflection which shows that the time reversal method has performance of temporal-spatial focusing, namely a time reversal guided wave can realize energy focusing on the defect.Theory analysis and numerical simulation demonstrate that the time reversal method can be used to enhance inspection energy for the guided wave inspection in pipe. The time reversal guided wave method is more favorable for the small defect inspection in pipes.