First‐order rate constants for the hydrolytic depurination of 2′‐deoxyinosine and its various (dien)Pt(II) ion complexes were measured over the acidic pH range. The rate profiles obtained indicate that the uncomplexed nucleoside and its N¹‐(dien)Pt(II) complex are depurinated via mono‐ and di‐protonated species, whereas the N⁷−(dien)Pt(II) and N¹, N⁷−di(dien)Pt(II) complexes exhibit significant spontaneous hydrolysis, which competes with a markedly retarded acid‐catalysed reaction. Rate constants for the various partial reactions were calculated and the results were employed to explain the effects that (dien)Pd(II) ion exerted on depurination rates of the same compounds. Similar measurements were carried out with the N¹, N⁷−di(dien)Pt(II) complex of 2′‐deoxyadenosine in order to further the understanding of the previously reported rate‐enhancing effect of (dien)Pd(II) ion on the depurination of 2′‐deoxyadenosine.