In the presence of the water-soluble iridium complex [Cp*Ir(H₂O)₃][OTf]₂, a variety of aldoximes, including aromatic, aliphatic, conjugated unsaturated and non-conjugated unsaturated, were converted into their corresponding amides in water with good to excellent yields. Further, the one-pot synthesis of amides from aldehydes, hydroxylamine hydrochloride and sodium carbonate via a tandem condensation–rearrangement reaction in water was also accomplished. Compared with the reported organometallic catalysts for the rearrangement of aldoximes to amides in water, the present catalyst exhibited some advantages such as being phosphorus ligand-free, having low catalyst loading, and operational convenience under air atmosphere.