The invention discloses a stainless steel welding electrode used for a third-generation nuclear power main pipeline and a production method of the stainless steel welding electrode, and belongs to the field of welding materials. The stainless steel welding electrode is composed of a chromium-nickel-molybdenum alloy welding core and a coating wrapped on the surface of the welding core, the welding core is composed of smaller than or equal to 0.020wt% of C, 1.00-2.50wt% of Mn, smaller than or equal to 0.30wt% of Si, 18.0-21.0wt% of Cr, 11.0-14.0wt% of Ni, smaller than or equal to 2.00-3.00wt% of Mo, smaller than or equal to 0.050wt% of Co, smaller than or equal to 0.050wt% of Cu, smaller than or equal to 0.010wt% of S, smaller than or equal to 0.015wt% of P and the rest Fe and impurities. Weight of the coating is 30-45% of that of the chromium-nickel-molybdenum alloy welding core. The method includes after uniformly mixing coating powder, adding a binder with the weight being 15-20% that of the coating for uniform mixing, feeding a mixture into a plodder to coat the mixture on the welding core, and subjecting the welding core to low-temperature baking and high-temperature baking. The stainless steel welding electrode has the advantages that content of ferrite in deposited metal is proper, and ferrite number FN of the deposited metal is 5-16; the deposited metal of the welding electrode is excellent in mechanical performance and meets nuclear power requirements; room temperature Rm is larger than or equal to 520Mpa, Rp0.2 is larger than or equal to 205Mpa, and A is larger than or equal to 35.0%; mechanical performance at high temperature of 350 DEG C includes that Rm is larger than or equal to 430Mpa, Rp0.2 is larger than or equal to 125Mpa, and A refers to actual measurement.