Dioxime oxalates, a type of carbonyl oximes, are well-known as clean sources of iminyl radicals that undergo key organic chemistry transformations. A series of dioxime oxalates is reported in this manuscript, obtained by the reaction of the corresponding oximes with oxalyl chloride and Et3N at room temperature. This one-pot method afforded three novel dioxime oxalates and the crystal structure of cyclopentanone dioxime oxalate analysis is also presented.