Presented have been the results of inventory estimation of anthropogenic beta-emitting Pu-241, in different components in the southern Baltic Sea ecosystem. The total Pu-241 activity present in the Gulf of Gdansk and the Gdansk Basin for 2021 was estimated at 1.99 TBq and 7.82 TBq, respectively, of which 1.59 TBq and 6.38 TBq in the sediments. The Vistula and the Neman River and the atmospheric fallout were distinguished as the primary sources of plutonium in these basins. In seawater of the Gulf of Gdansk, there was about 0.40 TBq Pu-241 (20.1% of total activity) and (1.44)TBq Pu-241 (18.4% of total activity) in the Gdansk Basin. The Pu-241 accumulated in living organisms in 2021 was 1.13 GBq in the Gulf of Gdansk and 3.96 GBq in the Gdansk Basin. In the Gulf of Gdansk biota, 55.7% was accumulated in zoobenthos, while in the Gdansk Basin, 48.3% was in zoobenthos.