In enzymology, a D-alanine 2-hydroxymethyltransferase (EC 2.1.2.7) is an enzyme that catalyzes the chemical reaction

5,10-methylenetetrahydrofolate + D-alanine + H₂O ${\displaystyle \rightleftharpoons }$ tetrahydrofolate + 2-methylserine

The 3 substrates of this enzyme are 5,10-methylenetetrahydrofolate, D-alanine, and H₂O, whereas its two products are tetrahydrofolate and 2-methylserine.

This enzyme belongs to the family of transferases that transfer one-carbon groups, specifically the hydroxymethyl-, formyl- and related transferases. The systematic name of this enzyme class is 5,10-methylenetetrahydrofolate:D-alanine 2-hydroxymethyltransferase. This enzyme is also called 2-methylserine hydroxymethyltransferase. This enzyme participates in one carbon pool by folate.