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The fibrinolytic enzyme, subtilisin D5, was purified from the culture supernatant of the isolated Bacillusamyloliquefaciens DJ-5. The molecular weight of subtilisin D5 was estimated to be 30kDa. Subtilisin D5 was optimallyactive at pH 10.0 and 45oC. Subtilisin D5 had high degrading activity for the Aα-chain of human fibrinogen and hydrolyzedthe Bβ-chain slowly, but did not affect the γ-chain, indicating that it is an α-fibrinogenase. Subtilisin D5 was completelyinhibited by phenylmethylsulfonyl fluoride, indicating that it belongs to the serine protease. The specific activity (F/C,fibrinolytic/caseinolytic activity) of subtilisin D5 was 2.37 and 3.52 times higher than those of subtilisin BPN’ and Carlsberg,respectively. Subtilisin D5 exhibited high specificity for Meo-Suc-Arg-Pro-Tyr-pNA (S-2586), a synthetic chromogenicsubstrate for chymotrypsin. The first 15 amino acid residues of the N-terminal sequence of subtilisin D5 areAQSVPYGISQIKAPA; this sequence is identical to that of subtilisin NAT and subtilisin E.