Diarrhea is one of the common causes of death in calf; it has significant economic impacts in cattle industry. Calf diarrhea is most complicated and has many factors, for example, environmental, management and nutritional. Many viruses like rotavirus, bovine viral diarrhea and corona virus play a very important role in causing diarrhea. Sixty pre-weaning calves were sampled. Samples were taken from four different places at Sulaimaniyah province (Kalar, HalbjaiShahid, Khurmal, and Sharazor) between September 2022 and March 2023.The animals were divided into 3 age groups: first group was (4–30 days), second group was (31–60 days), and third group was (61–90 days). Samples were being collected directly from diarrheic calves by rectal swab for PCR testing. A fragment of the partial N gene was amplified using the Taq DNA master mix (Addbio, Republic of Korea). Phylogenetic trees were constructed based on a partial fragment of the partial N gene. The results showed that the prevalence of bovine coronavirus was (10%) 6 out of 60 collected samples; in addition, the highest prevalence was in group 1 (4-30) day of age, while the lowest prevalence rate was in group 3 (61-90) days of age. This study reported the occurrence of Coronavirus for the first time in four different places in Sulaimaniyah province, northern Iraq, using genetic analysis.