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. 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 were 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. Conlusion : 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.