An austenitic stainless steel weld metal which has a chemical composition consisting of, by mass %, C: 0.05 to 0.11%, Si: 0.10 to 0.50%, Mn: 1.0 to 2.5%, P: 0.035% or less, S: 0.0030% or less, Co: 0.01 to 1.00%, Ni: 9.0 to 11.5%, Cr: 17.0 to 21.0%, Nb: 0.60 to 0.90%, Ta: 0.001 to 0.100%, N: 0.01 to 0.15%, Al: 0.030% or less, O: 0.020% or less, V: 0 to 0.10%, Ti: 0 to 0.10%, W: 0 to 0.50%, Mo: 0 to 0.50%, Cu: 0 to 0.50%, B: 0 to 0.005%, Ca: 0 to 0.010%, Mg: 0 to 0.010% and REM: 0 to 0.10%, with the balance being Fe and impurities, and satisfying [Nb−7.8×C≤0.25].