The correlation between the structure of organic mixed conductors and electrochemical device performance/stability has attracted much attention. In this research, we investigated the structure and properties of polymeric mixed conductors by fabricating the large-range crystallinity controlled polypyrrole via oxidative polymerization of two-monomer-connected precursors. The mixed conductivities and electrochemical characteristics were controlled by adjusting the stoichiometry of the connector versus the pyrrole monomer, and the results suggest that there exist two distinct domains: the low crystallinity domain where carrier concentration is well controlled, and the high crystallinity domain where hole mobility and ion mobility is finely tuned. We believe that our study can provide the general insight into the structure and properties of polymeric mixed conductors as well as the design principles governing OECT device performance and stability.