草酸钍是一种无机化合物，化学式为Th(C₂O₄)₂。

草酸钍可以由硝酸钍和草酸反应沉淀得到，沉淀物为六水合物。

Thorium oxalate is a white insoluble compound of thorium that is prepared by mixing a thorium nitrate solution in acid medium with an oxalic acid solution.

By mixing 0.5 M thorium nitrate solution with 0.5 M oxalic acid solution at room temperature thorium oxalate dihydrate ( Th(C₂O₄)₂.2H₂O ) is obtained. Thorium oxalate hexahydrate is obtained when precipitated from 2 M nitric acid solution. On heating to 500° it is converted to thorium oxide. The solubility product (Ksp) of thorium oxalate is 5.01 X 10 Density of anhydrous thorium oxalate is 4.637 g/cm.