The objective of the present study was to determine serum copper concentrations in sheep and goats infected with different gastrointestinal parasites. A total of 60 sheep and 30 goats were obtained from different areas in Mosul city and examined in the Veterinary Teaching Hospital, University of Mosul. Fecal and blood samples were collected from each animal. Animals infected with gastrointestinal parasites were diagnosed by detecting parasite eggs in fecal samples. Copper concentrations and hematological values were compared between infected and non-infected animals. Different gastrointestinal parasites were diagnosed include; Chabertia ovina, Cooperia spp., Haemonchus contortus, Marshallagia marshalli, Nematodirus spp., Oesophagostomum spp., Ostertagia ostertagia, Strongylus spp. and Trichostrongylus spp. in both single and mixed infection types. Infected sheep and goats suffered from different clinical signs such as emaciation, poor wool or hair, trembling, pale mucous membrane, loss of appetite, and diarrhea. Infected animals showed significantly (p≤0.05) lower serum copper concentrations compared to non-infected animals. Moreover, hematological parameters (RBC, Hb, PCV, MCH, MCV, and MCHC) were lower compared to non-infected animals. In conclusion, gastrointestinal parasitic infection in sheep and goats can decrease serum copper concentrations and blood parameters in infected animals, thereby exacerbating clinical signs.