The serum alpha-1 acid glycoprotein of 9 euthyroid subjects, 14 hypothyroid patients and 21 hyperthyroid patients was determined by radial immunodiffussion in agar plates. The serum alpha1 acid glycoprotein level in both the hypothyroid and hyperthyroid patients were significantly lowered when compared to the euthyroid subjects. There was no significant correlation between the alpha-1 acid glycoprotein level mid the Liothyronine resin uptake (T3 resin. uptake) and the serum total Thyroxine Iodide (T4I) level.