The current state and prospective of electric discharge methods of synthesis of carbon and metal–carbon nanomaterials (CNMs) in different areas of science, technology and industry are considered in the present paper. It was shown that as a result of electric discharge treatment of liquid hydrocarbons, the productivity of CNMs (namely, onion-like carbon, carbon nanotubes, carbon nanofibers and carbon thin films) in terms of the percentage of carbon, released from initial liquid as a nanomaterial, was 6.1% for pentane, 10.2% for hexane, 8.7% for cyclopentane, 14.4% for cyclohexane, 12.0% for benzene and 16.8% for kerosene. Component and phase composition of obtained products depends on the electrode material and composition of initial hydrocarbon liquid.