Abstract: Impact fretting wear test of alloy 690 tubes against the 405 stainless steel was performed through a small load impact wear testing machine in dry room temperature under different loads. The tube was fixed with cantilever beam, the alloy 690 tube and the 405 stainless steel which used as counterpart contacts with line. The test impact frequency was 10 Hz, the number of cycles was 10⁶, and varied loads were 5, 10, 20 and 40 N. The results show that the wear of alloy 690 tubes was increased with increasing of impact loads and cycles. In process of impact wear, the work hardening occurred on contact surface. With the increasing impact load, the work hardening became much greater. The wear mechanisms of impact fretting wear of alloy 690 tubes were abrasive wear and spalling, the oxidative behavior occurred on surface of tube. With increasing impact load, the oxidative behavior and abrasive wear became severe.