The invention provides the uses of fibrinogen-420 or alpha EC domain thereof, for inhibiting protein aggregation, refolding the denatured proteins, manufacturing drugs for prevention and/or treatment of protein misfolding diseases, resisting protein denaturation, and detecting the quality of protein products. The invention also provides the drugs for prevention and/or treatment of protein misfolding diseases or protein denatured disease, and the protein stabilizer. The active ingredient of the said drugs and stabilizer is fibrinogen-420 or alpha EC domain thereof.
