Thromboplastic plasma component (TPC), fibrinogen, and prothrombin were detd. quantitatively on plasma fractions obtained by a low temp, procedure. In dogs with exptl. pancreatitis, the TPC level was 2-8 times greater than the baseline. In patients with acute interstitial pancreatitis, the TPC values were 5-22 times the normal mean. The highest TPC elevations occurred several days after the serum amylase peaks.