The invention discloses a power distribution switch machinery characteristic on-line monitoring system and a monitoring method. The power distribution switch machinery characteristic on-line monitoring system comprises a power distribution switch, a power distribution terminal and main station waveform recording and analysis system which are successively connected. The power distribution switch has an operation mechanism and controls the on-and-off of the power distribution circuit through the operation mechanism and realizes the fault clearing, isolation and a node for load transferring; the power distribution terminal is matched with the power distribution switch for collecting voltage and the current waveform of the operation mechanism, performing statistic on the motion times of the switch, collecting the switch position signals, realizing the pre-processing and initial determination of the information, and uploading the data to the main station waveform recording and analysis system; and the main station waveform recording and analysis system receives the waveform transmitted by the power distribution terminal. The invention can retrieves the waveform of the operation mechanism of any power distribution switch and the machinery characteristic determination result on the power distribution terminal by the power distribution switch and realizes the fault alarm and fault positioning of the operation mechanism of the power distribution switch in order to provide the convenience to the maintenance staff to maintain.