Gadolinium oxalate is the oxalate of gadolinium, with the chemical formula Gd2(C2O4)3.

Its hydrate can be prepared by the reaction of gadolinium nitrate and oxalic acid.

[1] The decahydrate of gadolinium oxalate thermally decomposes to obtain the anhydrous form, which can then be heated to produce gadolinium oxide.

[2] Gadolinium oxalate reacts with hydrochloric acid to produce Gd(C2O4)Cl.

[3] It also reacts with sodium hydroxide under hydrothermal conditions to produce gadolinium hydroxide.