In enzymology, a cyanoalanine nitrilase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are 3-cyano-L-alanine and H<sub>2</sub>O, whereas its two products are L-aspartate and NH<sub>3</sub>.
This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in nitriles. The systematic name of this enzyme class is 3-cyano-L-alanine aminohydrolase. This enzyme is also called beta-cyanoalanine nitrilase. This enzyme participates in cyanoamino acid metabolism.