This dataset contains the source apportionment results for the dust fraction (<5 µm size fraction) of sediment core PS75/056-1 from the South Pacific Subantarctic Zone (55.16°S, 114.78°W; 3581 m water depth) collected during R/V Polarstern expedition ANT-XXVI/2 (PS75 BIPOMAC) in 11/2009-01/2010 (Gersonde, 2011, doi:10.2312/BzPM_0632_2011). The original lithogenic dust provenance signal was extracted from a total of 108 samples (incl. 13 full replicates) between 0.03 and 9.93 m core depth covering the period from ~8,000 to ~260,000 years before present. The age model is from van der Does et al. (2021, doi:10.1016/j.quascirev.2021.106978). The source apportionment was calculated using PS75/056-1 dust fraction radiogenic isotope compositions (doi:10.1594/PANGAEA.947018) and the Bayesian mixing model MixSIAR (Longman et al, 2018, doi:10.1038/s41598-018-24474-0; Stock et al., 2018, doi:10.7717/peerj.5096). Mean values of dust grain size reported together with the source apportionment results were previously published by van der Does et al. (2021, doi:10.1016/j.quascirev.2021.106978)). Iron (Fe) and Fe(II) flux data for PS75/056-1 (Shoenfelt et al., 2018, doi:10.1073/pnas.1809755115) were interpolated linearly to obtain values for the depths sampled for dust provenance work. The source-specific fluxes were calculated based on the relative contributions of the individual dust source regions to the total Fe input.