Partial discharge（PD）of transformer bushings causes degradation of the insulation

resulting in fire and explosion of the bushing. The conventional PD measurement method needs to use the grounding lines of bushing’s end screen

making the operation complex

and the measurement is interfered by the pulse signal from grounding network. In order to solve this problem

this study proposed a partial discharge detection and pattern recognition method for the bushing based on ultra-high frequency technology. According to the typical defects in real bushings

four PD defect models were designed on a 110 kV transformer bushing. Then the PD signals of the four defect models were detected by the conventional pulse current method and the proposed UHF detection method

respectively. The results show that: 1)the PRPD spectrums of the PD defects obtained by the UHF detection method and the pulse current method are basically identical; and 2)the PD defect types and possible discharge position can be identified according to the morphological features of the PRPD and NV spectrums. This research may promote on-line PD detection of bushings.