In enzymology, oxamate carbamoyltransferase () is an enzyme that catalyzes the chemical reaction
The enzyme converts oxamic acid to oxaluric acid, with inorganic phosphate as a byproduct.
This enzyme belongs to the family of transferases that transfer one-carbon groups, specifically the carboxy- and carbamoyltransferases. The systematic name of this enzyme class is carbamoyl-phosphate:oxamate carbamoyltransferase. This enzyme is also called oxamic transcarbamylase. This enzyme participates in purine metabolism.