Abstract: Through analysing characteristics of energy detection and high-order spectrum detection,methods of Power-Law detection based on energy detection and high-order spectrum are studied according to traits of underwater acoustic transient signals.For better use of statistic information in underwater acoustic transient signals,these two detectors are jointed to be a dual-channel Power-Law detector,which validity is proved through simulation experiments.It can adapt to more complex underwater acoustic environment and improve detection performance for underwater acoustic transient signals.