Using Hansel's stain, eosinophiluria greater than 5% of total urinary white blood cells was found in 59% of a randomly selected population sample in an area endemic for schistosomiasis hematobium. The prevalence and mean level of eosinophiluria were significantly higher in infected subjects than in noninfected subjects (P < 0.05). The sensitivity (80%), specificity (86%), and positive predictive value (82%) of eosinophiluria as a diagnostic index for schistosomiasis hematobium were significantly higher (Youdin index 0.66; P < 0.05) than those of proteinuria, hematuria, and leukocyturia taken singly or in combination. However, unlike the latter three measurements, this method involves microscopy. There is a great need for a chemical method for measuring eosinophiluria.