The invention discloses a method for the lossless capturing of a partial discharge nanosecond-level narrow pulse sequence, and the method comprises the steps: designing a combined triggering strategyof a high-speed collection device for signal capturing; carrying out the continuous sampling of a part, meeting with the combined triggering strategy, of a signal through the high-speed collection device, and extracting nanosecond-level narrow pulses from the continuously sampled signals to form the nanosecond-level narrow pulse sequence; analyzing the nanosecond-level narrow pulse sequence, and calculating the pulse width and the pulse interval; and configuring a quick storage mode and parameters of a collection card according to the pulse width and the pulse interval of the nanosecond-levelnarrow pulse sequence. The method achieves the capturing of the nanosecond-level narrow pulse sequence, and solves a technical problem that the automatic lossless collection of a partial discharge signal cannot be achieved in the prior art. The method reduces the data processing burden of the device, and improves the work efficiency. The method avoids the detection leakage or signal distortion, and improves the accuracy in judging a fault type.