In this work, the effect of mullite dopant (mull) on the structural and electrical properties of two conductive polymers: polyaniline (PAni) and polypyrrole (PPy), which have great interest in science and materials engineering, has been evaluated. Doped polymers were synthesized with different contents of mineral and at two polymerization times (tP) by an in situ chemical synthesis in acidic aqueous solution and using Ammonium Persulfate (APS) as the reaction initiator. Structural characterization was performed by X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The conductivity values (σac) were estimated from Electrochemical Impedance Spectroscopy (EIS). It was found that, at concentrations of work, were obtained higher values σac of conductivity at the highest concentration of the mineral, however, in some compounds the conductivity decreased. The variations in conductivity were attributed to PC-dopant interactions.