Cyclospora has been identified as one of the most important intestinal pathogens causing protracted diarrhea in animals and human beings.In China,Cyclospora infection in humans has been reported in Anhui,Zhejiang and Henan provinces.Several studies indicated the non:human primates have the closest genetic relationships with humans.Therefore,determination of Cyclospora spp.in monkeys would have important implications for controlling Cyclospora infection in humans.To determine the Cyclospora species in the non:human primate Rhinopithecus roxellanae,a total of 71 fecal samples from 19 endangered snub:nosed monkeys in Shaanxi province were collected and examined using Sheater s sugar flotation technique and by sequencing the fragments of 18S rDNA.Only two Cyclospora isolates from 2 golden snub:nosed monkeys (R.roxellanae) were obtained and identified between July 2011 and August of 2012.The sequences of the 18 S rDNA for the two Cyclospora isolates were 477 bp,with no nucleotide variation between them.Phylogenetic analysis based on the 18S rDNA sequences revealed that the two Cyclospora isolates were posited into the clade Cyclospora spp.and sistered to C.colobi.These results firstly showed that Cyclospora infection occurred in R.roxellanae in hot and rainy weather,which would provide useful information for further understanding the molecular epidemiology of Cyclospora spp.and the control of Cyclospora infection in non:human primates as well as in human beings.