Iodine doping of polyferrocenylenesilylene(germylene) thin films, [(η5-R2EC5H4)Fe(η5-C5H4)]n, E = Si, Ge, transforms them from insulators to conducting materials. The process was monitored by IR, Raman, and UV/vis spectroscopy and occurs via irreversible electron transfer to form of ferrocenium ion centers with [I3]- counteranions. The latter further react with I2 to form [I5]- polyiodide anions in a reversible manner. A Mossbauer spectrum of the doped polymer suggests that alternate Fe centers have been oxidized. Treatment of the doped films with NH3 results in a typical compensation process.