Smooth, densie and uniform nano-crystalline diamond-like-carbon (DLC) film is deposited on an optical glass substrate by pulsed high energy density plasma(PHEDP) gun charging in nitrogen atmosphore. Scanning electron microscope, Raman spectra and EMSA show that, the grain size of the DLC film is less than 20nm; there are a number of nitrogen atoms and nano-crystalline diamond in the DLC film. The sheet resistance of this film is larger than 109Ω/sq. When the change voltage is lower and charge distance is longer, the deposited film is loose. Theoretic analysis show that, at higher charge voltage, the deposited grain is larger, with longer charge distance, the collision force between deposition grain and substrate is weaker. The theoretic results are in agreement with the experimental conclusion.