Field-emission studies were carried out on diamond-like-carbon (DLC) and nitrogen-doped diamond-like-carbon (N-DLC) films deposited by an electro-deposition technique. The films were deposited on Si(100) substrates by electrolysis of methanol–urea solution under high voltage, at atmospheric pressure, and low temperature. The microstructure and morphology of the resulting films were analyzed by means of Raman spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy. The field-emission measurements were carried out with a parallel plate configuration using the deposited DLC and N-DLC films as the cathode and indium tin oxide coated glass as the anode. The field-emission measurements indicated that the electro-deposited films exhibited good field-emission properties and the nitrogen doping could increase the current density. These behaviors were demonstrated to mainly relate to changes in the microstructure of the samples, in connection with the difference of surface morphology.