The prevalence of Cryptosporidium parvum infection in cattle raised in 7 provinces, such as: Son La, Nghe An, Quang Binh, Quang Tri, Thua Thien-Hue, Quang Nam, Dac Lac and Hanoi was determined by PCR technique. The investigated results showed that: - The prevalence of Cryptosporidium parvum infection in cattle raised in the above mentioned provinces was relatively high, varying from12.40 to 60.98 percent. - The prevalence of C. parvum infection in cattle raised concentratively in-door was 50.04 percent, that was higher than that of cattle raising out-door (29.23 percent). - The prevalence of C.parvum infection in cattle infected with diarrhea (58.38 percent) was higher than that of cattle uninfected with diarrhea (28.18 percent).- The prevalence of C. parvum infection did not depend on age or sex of cattle.