Gold(II) sulfate is the chemical compound with the formula AuSO4 or more correctly Au2(SO4)2. This compound was previously thought to be a mixed-valent compound like AuIAuIII(SO4)2, but it was later shown that it contained the diatomic cation Au4+2, 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.