Selenium is one of the compounds belonging to the trace minerals group, which needs less than 100 mg/day. This element is one of the main constituents of selenoproteins, and the function of selenoproteins is to help make DNA and protect cells from damage and infection. This experiment aimed to evaluate the effect of different sources of selenium on some mineral elements in the blood serum of lambs. This experiment was conducted using twenty 4-month-old lambs with an average weight of 37±2.2 kg, 4 treatments, and 5 replications in a completely randomized design (CRD). The treatments tested included control, sodium selenite, nano selenium, and VitEsel. The experiment duration was 30 days, and blood sampling of lambs was performed at the beginning of the experiment (zero), 15, and 30 days. Different sources of selenium significantly affected the concentrations of iron, copper, and zinc (P<0.05). Different sources of selenium in this experiment decreased the concentration of iron and copper and increased the concentration of zinc and plasma selenium in different periods (P<0.05). Using different sources of selenium changed the concentration of the studied elements and showed the difference in their bioavailability.