This dataset is based on data obtained during the synchronous mid-winter counts of waterbirds in the Azov–Black Sea region of Ukraine, as well as at specific sites along the Dnipro River (from Kyiv Region to Zaporizhzhia Region) and at certain wetlands near the city of Zhytomyr, conducted in the winter seasons of 2017/2018, 2018/2019, 2019/2020, 2020/2021, and 2021/2022 within the framework of the International Waterbird Census (IWC) and the Regional Ornithological Monitoring (ROM) programmes. It comprises 3,471 records of more than 1.4 million individuals, predominantly waterbirds, representing 75 species, 18 families, and 11 orders. The dataset is based on data published in issue 16 of the Bulletin ROM (Bulletin ROM. Issue 16. Results of International Waterbird Census (IWC) in Ukraine in 2018–2022 / Edited by Yu. O. Andryushchenko, V. A. Kostiushyn. – 2023. – 72 p.). The Azov–Black Sea region lies within the steppe zone of southern Ukraine. It plays an important role for bird migration and wintering, particularly for waterbirds, as the combination of natural habitats provides favourable conditions for resting and feeding. The region stretches for about 800 km. Within its boundaries there are 23 wetlands of international importance with a total area of 767,396.3 ha, of which 19 sites were covered, to a greater or lesser extent, during the mid-winter counts in 2018–2022.