In this work, we investigate the ion conductivity mechanism of a metal-ligand coordinated polymer by designing of the model system consisting of pyridyl imine functionalized PDMS and two metal cations Li + and Cu 2+ . We first confirm that the formation of metal-ligand complex promotes ion dissociation in the polymer matrix by showing increased ionic conduc-tivity of the ligand-functionalized PDMS compared to the pristine PDMS. MD simulations prove that cation-anion dissociation is facilitated by the interaction of metal cations and ligands attached to the polymer. Based on this finding, a series of Li + coordinated PDMS with different counter anions of the salt are synthesized to investigate the effect of cation-anion interactions on the ionic conductivity of the polymer. We find that a bulkier anion not only yields the stronger Li + -ligand coordination but also suppresses the tendency for ion precipitation, promoting higher ionic conductivity. In addition, MD simulations show that bulkier anions with higher delocalized charge tend to have more frequent intercluster hopping and form more negatively charged clusters. The effect of salt concentration is next studied, which is seen to first enhance the ionic conductivity of the complex by increasing the ion concentration. However, for the Li + cation systems, the ionic conductivity reaches the maximum when the ligand coordination capacity is saturated, and then starts to decrease at the higher salt concentrations since the additional salt preferentially forms clusters. MD simulations confirm that the chain segmental motion is also hindered by increasing salt loading, though this seemed to be of secondary influence for the Li + system. The temperature-dependent ionic conductivity of the Li + coordinated PDMS shows an Arrhenius relation, indicating that the strength of metal-ligand coordination and cation-anion interaction are the rate-determining factors in the ion transport.