To provide a catalyst with high yield of unsaturated carboxylic acid used when unsaturated aldehyde is catalytically oxidated with molecular oxygen in a vapor phase to synthesize unsaturated carboxylic acid, and a method for manufacturing the same.

The method is provided for manufacturing a catalyst for synthesizing unsaturated carboxylic acid when unsaturated aldehyde is catalytically oxidated with molecular oxygen in a vapor phase to synthesize unsaturated carboxylic acid, wherein the solution is sintered at the maximum temperature of 300C or more and 700C or less while circulating the gas of 1.5 l/h or more and 4.0 l/h or less per 1 g of a catalyst precursor containing ammonium radicals or a nitrogen-containing organic compound.