The invention discloses a diagnosis graph phase windowing parameter adjusting method based on partial discharge signal characteristics, and the method includes, firstly, acquiring a discharge pulse sequence of the partial discharge signal, and calculating the pulse width and the pulse interval of the discharge pulse sequence; adjusting the phase windowing parameters converted from the partial discharge signals into the diagnosis graph according to the pulse width and the pulse interval, containing all the discharge pulses in each phase window; and converting the partial discharge signals intoa diagnosis graph according to the phase windowing parameters. According to the method, the extraction precision of the partial discharge pulse information is improved, and the problems that when a current discharge pulse signal is converted into a diagnosis spectrum, the partial discharge pulse phase windowing number is not enough, the corresponding phase precision and the time precision are toolow, and the pulse signals are not distinguished to be lost, the signal key information is lost and the diagnosis result is affected are solved, and the diagnosis efficiency and accuracy are improved.