Through tension testing in single wire and cables, acoustic emission (AE) waveform were gained from wire crack expansion, wire breakage and cables damage. Comparing the waveform, spectrum and time-frequency characteristics in different sources, the results illustrate that, energy and continuous time of wire breakage are more higher than crack expansion signals, however, its amplitude is largish to the most value of crack expansion; The spectrum peak of wire breakage is very obvious, mostly at 43KHz, the vast majority energy distribute in a equal frequency banding in whole continue time; The spectrum of crack expansion signal contain four frequency band, maximum energy at 50-60KHz, and the high frequency part appear at the front wave, which will quickly disappears along with the time increase; While the wire breakage source propagate in the cable, its energy will attenuates and energy contained in low frequency will increase relatively..