A survey was conducted to determine of Bovine Viral Diarrhea Virus, Bovine Herpesvirus 1 and Bovine Leukosis Virus infections in a dairy cattle herd with abortion problem in Çankırı. A total of 172 serum and 172 leukocytes samples were collected from unvaccinated Holstein cows for mentioned infections in 2010. All sampled animals were over 3 years. While the serum samples were analysed by commercially available indirect enzyme linked immunosorbent assays (ELISA), leukocyte samples were analysed by direct ELISA. Out of 172 serum samples 106 (61.62%) were found to be positive for BVDV antibodies. None of 172 cattle leukocyte samples were positive for BVDV antigen. Antibodies against BHV-1 and BLV were not detected in any serum samples. The findings imply that antibodies to BVDV infections are widely distributed in this herd. In this farm, cows have not been previously vaccinated for BVDV, thus seropositive results indicate that there was an acute BVDV infection in cattle. Cows should be routinely checked for BVDV status. Seronegative results for BHV-1 and BLV can be explained by the management conditions. As the negative results of BHV-1 and BLV assessed as positive in terms of herd. In conclusion, it is considered that viral agents can play an important role in abortion in cattle and these factors should be checked regularly. Furthermore it is always taken into consideration viruses may also lead to reproductive problems on cattle breeding.  A survey was conducted to determine of Bovine Viral Diarrhea Virus, Bovine Herpesvirus 1 and Bovine Leukosis Virus infections in a dairy cattle herd with abortion problem in Çankırı. A total of 172 serum and 172 leukocytes samples were collected from unvaccinated Holstein cows for mentioned infections in 2010. All sampled animals were over 3 years. While the serum samples were analysed by commercially available indirect enzyme linked immunosorbent assays (ELISA), leukocyte samples were analysed by direct ELISA. Out of 172 serum samples 106 (61.62%) were found to be positive for BVDV antibodies. None of 172 cattle leukocyte samples were positive for BVDV antigen. Antibodies against BHV-1 and BLV were not detected in any serum samples. The findings imply that antibodies to BVDV infections are widely distributed in this herd. In this farm, cows have not been previously vaccinated for BVDV, thus seropositive results indicate that there was an acute BVDV infection in cattle. Cows should be routinely checked for BVDV status. Seronegative results for BHV-1 and BLV can be explained by the management conditions. As the negative results of BHV-1 and BLV assessed as positive in terms of herd. In conclusion, it is considered that viral agents can play an important role in abortion in cattle and these factors should be checked regularly. Furthermore it is always taken into consideration viruses may also lead to reproductive problems on cattle breeding.