Introduction and objective: The war and the humanitarian crisis in Ukraine have resulted in a mass migration of millions of Ukrainians into the EU countries. According to the data obtained from Statistics Poland, a governmental agency collecting and publishing the country’s statistical data, the number of Ukrainian children currently living in Poland is approximately 500,000. The massive influx of immigrants into Poland poses a considerable challenge to the national health care sector. The aim of this study was to assess the prevalence of intestinal parasitic infections among Ukrainian child war refugees living in Warsaw. Material and methods: The study involved a total of 25 Ukrainian children, patients of the Clinic of Paediatrics, Nephrology and Paediatric Allergology at the Military Institute of Medicine – National Research Institute in Warsaw. Parasitological diagnostic work-up was carried out in October 2023 at the Department of Epidemiology and Tropical Medicine, the Military Institute of Medicine – National Research Institute in Gdynia. Stool tests for the presence of intestinal parasites were conducted by light microscopy using three different methods (direct smear in Lugol’s solution, decantation with distilled water, Fülleborn’s flotation). Results: A total of 20% of the children studied (5/25) were found to be infected with potentially pathogenic stramenopile Blastocystis spp. In addition, two of the children were also infected with non-pathogenic Endolimax nana and Entamoeba coli protozoa. There were no infections with nematodes, cestodes or trematodes among the study participants. Conclusions: The confirmation of potentially pathogenic Blastocystis spp. in stool samples collected from Ukrainian children, war refugees living in Warsaw, justifies the necessity to re-introduce a large-scale routine screening for intestinal parasites in the paediatric population in Poland.