The residual quantity of tri-Bu phosphate (TNBP) in freezing human fibrin sealant kit was determined by GC.HP-20M column was used with tri-Pr phosphate (TPP) as the internal standardThe injector, detector, and column temperature were 190, 210, and 140°, resp.The carrier gas was N2.The standard curve was linear in the range of 2-16 μg mL- 1 (r = 0.999 5).The average recovery was 100.2% (RSD 2.78%).