The invention relates to a bandpass filtering device for carrying out partial discharge online monitoring through remote control band selection. The device comprises a pulse current sensor, a multi-band bandpass filter, an analog to digital converter and an upper computer which are connected in sequence. A narrowband bandpass filtering module and an automatic band selection module are arranged in the upper computer. The automatic band selection module and the multi-band bandpass filter are connected. The working process of the system is that the pulse current sensor collects a detection waveform; the band of the multi-band bandpass filter is automatically selected by employing the automatic band selection module; broadband filtering is carried out; the signal output by the multi-band bandpass filter is converted into a digital signal; the digital signal is sent to the upper computer; and narrowband filtering is carried out through the narrowband filtering module. Compared with the prior art, the device has the advantages of high precision and high sensitivity.