Considering cable accessories structure and the characteristic that insulation failure easily occurs in internal attachment resulting in partial discharge, this paper designed a built-in UHF and UWB bowtie antennas sensor to detect partial discharge signal for cable accessories. Simulation results show that the effective bandwidth of the antenna is 350~585 MHz. Measurement results also show that the antenna sensor has high sensitivity and superior performance, and can be applied to PD UHF signal detection of cable accessories.