Metalloenzyme was purified from the fruiting bodies of Tricholoma sejunctum. MALDI-TOF and ICP/MS analyses revealed that the enzyme had a molecular weight of 18788.25 and includes $Zn^{2+}$ ion. The N-terminal amino acid sequence of the enzyme was Ala-Thr-Tyr-Lys-Ile-X-Ser-Ala-Thr-His-Gln-X-X-Leu-Val. The activity of the enzyme was inhibited by EDTA and 1,10-phenanthroline, indicating that the enzyme was a metalloprotease. No inhibition was found with E-64 and pepstatin. It has broad substrate specificity for synthetic peptides. The enzyme was stable up to $40^{circ}C$. The activity of the enzyme was increased by $Zn^{2+}$ and $Co^{2+}$, while it was totally inhibited by $Hg^{2+}$. The enzyme hydrolyzes $A{alpha}$ subunit of human fibrinogen but did not show any reactivity for $B{eta}$ and ${gamma}$ form of human fibrinogen.