a total of 500 fecal samples from dairy and beef calves were screened for Cryptosporidium using ICT kits. Results of rapid screening test detected 80 positive samples (16 %) for Cryptosporidium infection. Out of 80 samples, Cryptosporidium infection was found in 67 samples with infection rate of (13.4%) by using nested PCR technique. Infection rate of Cryptosporidium by nested PCR was 14.4% (45/312) in calves aged from 3 to15 days, however the infection rate in age groups of 16-30 days and 31-50 days was reduced. Depending on the breed of calves, Cryptosporidium species were detected in 32 of 250 beef calves and in 35 of 250 dairy calves. Moreover, Cryptosporidium infection was widely spread in all sampling locations although the geographic nature of Japan where prefectures are far apart. Southern prefectures revealed the highest infection rates whereas; the northern regions showed the lowest infection rates.