Gold(II) sulfate is the chemical compound with the formula or more correctly . This compound was previously thought to be a mixed-valent compound like Au<sup>I</sup>Au<sup>III</sup>(SO<sub>4</sub>)<sub>2</sub>, but it was later shown that it contained the diatomic cation , making it one of the first known examples of an inorganic gold(II) compound. The bond distance between the gold atoms in the diatomic cation is 249 pm.
Gold(II) sulfate is produced by reaction of sulfuric acid and gold(III) hydroxide. Gold(II) sulfate is unstable in air and oxidizes to hydrogen disulfoaurate(III) ().