Giardia sp. was found in the white stork (Ciconia ciconia) in The Netherlands for the first time. The Giardia sp. trophozoites that were found in the feces of a 6-wk-old white stork, were examined by light microscopy. The parasites closely resembled Giardia ardeae that had been isolated by others from several species of wading birds belonging to the order Ci-coniiformes, sharing a deeply notched adhesive disk, a single caudal flagellum, and a single round median body. Serologically, the parasites did not react with anti-Giardia intestinalis monoclonal antibodies. Although no signs of intestinal disease were observed in the stork chick, the presence of parasites in all stages of development and the huge number of parasites show that the stork chick was experiencing an active infection with G. ardeae type parasites.