The invention provides an ultrahigh-intensity all-austenite stainless steel welding wire, and relates to a stainless steel welding wire. The welding wire comprises the following chemical ingredients in percentage by mass: 0.05 to 0.3 percent of C, 0.50 to 1.20 percent of Si, 10 to 15.0 percent of Mn, 16.0 to 20.0 percent of Cr, 3.0 to 7.0 percent of Ni, 0.01 to 0.03 percent of Ti, 0.1 to 0.30 percent of N, 0.15 to 0.30 percent of V, at most 0.010 percent of S, at most 0.020 percent of P and the balance Fe. The ultrahigh-intensity all-austenite stainless steel welding wire is applicable to all-position welding, the welding quality is good, meanwhile, the welding efficiency is also greatly improved, multi-time performance tests prove that when the welding wire is adopted for welding Mn13 steel, the welding seam metal intensity reaches higher than 730 MPa, the toughs reaches about 100J, the performance index requirement is met, in addition, the preheating-free welding is realized, the heat treatment is not needed after the welding, and the welding process is simplified. Compared with a traditional welding wire with the same alloy content, the welding wire provided by the invention ahs the advantages that the intensity of melted metal is improved by 150MPa, in addition, the low-temperature impact is improved by 20J, the result shows that the weld metal integral performance of the welding wire is excellent, in addition, the cost is lower, and higher cost performance is realized.