The objective of this study was to determine serum thyroid hormones (Thyroxine T₄, Triiodothyronine T₃) and the anterior pituitary secretion Thyroid Stimulating Hormone (TSH) in normal healthy donkeys in Sudan. Detection of such hormones was done using Radio-immune assay (RIA) and immuno-radiometric assay (IRMA) techniques. The obtained values (mean ± standard deviation, SD) of male and female animals were comparable. The mean values for serum thyroxine (T₄) were 8.46 ± 7.19 (1.40 - 25.73) ng/ml, the serum triiodothyronine (T₃) 0.52 ± 0.21 (0.20 - 1.03) ng/ml, and thyroid stimulating hormone (TSH) were 0.86 ± 0.13 (0.64 - 1.15) mIU/L.