The present study was performed in order to clarify the significance of serum amyloid A(SAA) estimation for the diagnosis of bovine amyloidosis and SAA as a useful parameter for the health status in herds. Twelve dutch dairy cows with final diagnosis(2 with amyloidosis, 3 with acute inflammatory disease and 7 with chronic inflammatory disease) were used to charify the significance of SAA determination for the diagnosis of bovine amyloidosis. The SAA concentration in the group of inflammatory disease was higher than that of amyloldotic group. Further the SAA value in the group of acute inflammatory disease was higher than that of chronic ones. To clarify the significance of SAA estimation as a useful parameter for the health status in herds, two Korean dairy farms(A and B) were selected and the SAA concentration was determined in total 76 cows(49 from A farm and 27 from B farm). The SAA concentration in cows from A farm was ranged with 0～169%. The cows with high level of SAA(31～169%) had the disease histories(1 with retained placenta, 3 with chronic mastitis, 2 with acute mastitis, 1 with abortion and acute mastitis, 1 with ovarian dysfunction, 1 with downer cow syndrome and 1 with laceration of the teat). The SAA value in the cows from B farm was ranged with 0～29% and disease history was not detected. In conclusion the SAA determination only is thought to be difficult for the diagnosis of bovine amyloidosis. Furthermore SAA estimation is thought to be a useful parameter for the health status in herds.