This study was carried out to determine the prevalence of verotoxic E. coli O157:H7 in beef dairy cattle at National Animal Production Research Institute (NAPRI). A total of 120 faecal samples were obtained between May – July. The samples were enriched at the point of collection using modified tryptone soya broth (MTSB) and incubated at 37oC for 24hr on arrival to the laboratory. From the enrichment medium a loop full of the samples were obtained and streaked on EMB plates. The plates were labeled and incubated at 37o C for 24hour. The colonial morphology on each plate was then appraised and those colonies with greenish metallic sheen were considered to be E. coli. These were then stored on Nutrient agar (NA) slants and incubated at 37o C for 24hr. the slants were then stirred at 4oC awaiting biochemical test. After sample collection and preservation of the positive organism on Nutrient agar (NA) slants. Gram staining was carried out to differentiate the bacterial species into two large groups based on their cell wall constituents. All colonies that were considered E. coli after Gram staining were further screen biochemically which involves the observation of whether or not a growth of bacterium in liquid medium will ferment a particular gas. The selected colonies were later plated on Cefixime Tellurite Sorbitol MacConkey Agar (CT-SMAC) for 24hour. E. coli O157H:7 was characterized as colourless colony as it does not ferment sorbitol but uses peptone as source of energy thereby liberating ammonia (NH3) which increase the pH of the medium making the colony to appear colorless. The result of the study reveals that sex and age of cattle showed significant association with the organism. The highest prevalence was found in female weiner (16.6%), cow, bull, female calf, female weiner, male haifer, male calf and male weiner showed zero prevalence of E. coli 0157:H7 except female heifer with (25%) prevalence.