The invention discloses a double-principle cable partial discharge sensor, mainly comprising a capacitive sensor and an inductive sensor which are sleeved outside a cable shielding layer, wherein thecapacitive sensor comprises an inner layer plate, a waterproof layer and an outer layer plate in order from inside to outside, and the inner layer plate is wrapped on the outer sheath of the cable; the inductive sensor comprises an open circular coil bobbin, a coil uniformly wound on the coil bobbin, and a metal shell; the coil bobbin is made of a material with high magnetic permeability, the metal shell is disposed outside the coil bobbin; and the inductive sensor is disposed outside the capacitive sensor. A data fusion method of the sensor is also disclosed, which fully utilizes the characteristics of the dual-principle sensor with sub-band complementation and white noise uncorrelated, and combines the low-frequency/high-frequency performance of sensors with different principle to betterrestore the waveform with a frequency division weighted algorithm, thereby achieving efficient extraction of the partial discharge signal of the cable.