The prevalence of Cryptosporidium spp. and Giardia spp. in healthy asymptomatic cows and calves was investigated on 30 farms in sarkisla in Sivas. The population on these farms consisted of 457 animals: 47 calves 15-45 days old, 48 calves 45-90 days old, 38 calves 90 days-6 months old, 254 calves 6 months-1 year old, 60 cattle 1-3 years old, and 10 cattle 9-15 years old. Cryptosporidium spp. oocysts were identified by zinc sulphate flotation technique and modified acid fast stain methods in cattle ranging from 15 days old to adults. Cryptosporidium spp. positive animals were found at all (100%) farms. The overall prevalence of Cryptosporidium spp. was 70.3% and 31.4% in cows and calves, respectively. The prevalence of Cryptosporidium spp. was significantly (Chi(2) = 39.00: P < 0.05) lower in calves than in adults.