The invention relates to a process for producing oxamide-functional siloxanes by reacting (A) siloxanes of the general formula (I) with (B) siloxanes selected from (B1) linear siloxanes of the general formula HO[SiR2O]tH  (II) and (B2) cyclic compounds of the general formula (SiR42O)s  (III), wherein the radicals and indices have the definitions specified in claim 1, in the presence of (C) catalysts.