Several new palladium(II) complexes containing acetoxime as a unidentate ligand were synthesized from cis-[Pd(en)(solv)2]²⁺ 1a and cis-[Pd(dtod)(solv)2]²⁺ 1b, in which the displaceable ligand solv is water or acetone, en is ethane-1,2-diamine, and dtod is 3,6-dithia-1,8-octanediol. The acetoxime complexes are characterized by UV-visible spectrophotometry and ¹H and ¹³C NMR spectroscopy in solution. Acetoxime in the mono-oxime complexes cis-[Pd(en){N(OH)C(CH3)2}(solv)]²⁺ 2a and cis-[Pd(dtod){N(OH)C(CH3)2}(solv)]²⁺ 2b undergoes hydrolysis to acetone and hydroxylamine. The proposed mechanism involves internal attack of a Pd^II-bound hydroxo ligand at the coordinated acetoxime. This palladium(II)-catalysed hydrolysis is at least 10⁴ times faster than hydrolysis in the absence of a catalyst. The rate enhancement arises from polarization of acetoxime upon coordination to palladium(II), the availability of the nucleophilic hydroxo ligand, and close proximity of these two species. The complex [Pd(dien){N(OH)C(CH3)2}]²⁺, which contains the tridentate diethylenetriamine ligand, is almost unreactive toward hydrolysis because it lacks a Pd^II-bound aqua or hydroxo ligand, so that the reaction occurs via the less-favorable external attack of solvent water. Acetoxime in the bis-acetoxime complex cis-[Pd(dtod){N(OH)C(CH3)2}2]²⁺ 3b hydrolyses very slowly because this complex also lacks aqua or hydroxo ligands. Therefore, this complex was crystallized and its structure determined by X-ray crystallography.