The invention relates to an electric welding rod used for manual welding. The electric welding rod comprises core welding-wires containing the following chemical compositions (wt%): 0.020-0.100 of C, 0.350-0.550 of Mn, 0.015-0.030 of Si, 0.005-0.015 of P, 0.002-0.005 of S, 0.01-0.20 of Cr, 0.01-0.30 of Ni, 0.01-0.20 of Cu, 98.675-99.47 of Fe, and the residue of impurity; the electrode coating comprises the following compositions: 28-38 of marble powder, 16-28 of fluorite powder, 2-8 of feldspar powder, 2-7 of white titanium pigment, 4-8 of electrolytic manganese, 3-7 of ferrosilicon powder, 6-9 of ferrotitanium powder, 0.5-2 of ferromolybdenum powder, 3-8 of nickel powder, 10-25 of iron power and 5-8 of other elements. The chemical compositions, the performance and the structure of the welding seam of a grade X80 steel pipe welded by using the electric welding rod are closer to the pipe body, and without heat treatment, the welding seam can meet the requirements on technical indicators such as high strength, high toughness, low hardness and the like of the grade X80 steel pipe used for oil and natural gas transferring; the electric welding rod overcomes the defaults in the prior art that the welding seam is required to be heat-treated after welding, the quality is poor, and engineering accidents are easy to happen when in use and the like.