Polyaniline (PAn) thin films were prepared from aniline solutions in by scanning the potential cyclically between −0.2 and 0.8 V (vs. SCE). Films of different thicknesses, and hence different intrinsic oxidation states, reacted differently with . While redox reactions leading to the deposition of silver metal occurred between Ag+ and PAn in thick films (≥40 deposition cycles), thin films (≤20 deposition cycles) favored the formation of a metal cation‐polymer complex. The valency of silver in the polymer was determined by electrochemical measurements and x7hyphen;ray photoelectron spectroscopy. Changes in polymer morphology due to the treatment were examined by scanning electron microscopy. It is suggested that the interactions between PAn and Ag+ could be applied to electrocatalysis and to the recovery of silver from aqueous solutions.