Objective:To study the Cryptosporidium infection among young children in Anhui province, and to explore the best way to diagnose the disease. Methods: Stool specimens of 1 204 children were collected; oocysts of Cryptosporidium were identified with auramine O-modified staining, acid-fast staining, safranine T and methylene blue staining, and auramine O-modified acid-fast staining. Results: The detectable rate of Cryptosporidium in four stainings were respectively 2.46%, 1.50%, 1.98% and 3.46%, and there was a higher significant difference in the rate between auramine O-modified acid-fast staining and the others(P < 0.005). The detectable rate was significantly lower in urban children(2.14%, 15/684) than in rural ones(5.19%, 27/520). Boys and girls had similar detectable rate (1.99%, 24/1 204 vs. 1.50%, 18/1 204). Cryptosporidium infection was usually subclinical, and its major clinical features included benign diarrhea, mild abdominal pain and nausea. Conclusion:Cryptosporidium infection was relatively common in kindergartens and a higher infection rate was found in rural children. As the majority of the Cryptosporidium infections were subclinical, diagnosis is important although difficult.