In enzymology, an anthranilate N-methyltransferase (EC 2.1.1.111) is an enzyme that catalyzes the chemical reaction

S-adenosyl-L-methionine + anthranilate ${\displaystyle \rightleftharpoons }$ S-adenosyl-L-homocysteine + N-methylanthranilate

Thus, the two substrates of this enzyme are S-adenosyl methionine and anthranilate, whereas its two products are S-adenosylhomocysteine and N-methylanthranilate.

This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:anthranilate N-methyltransferase. This enzyme is also called anthranilic acid N-methyltransferase. This enzyme participates in acridone alkaloid biosynthesis.