Double layer structures of porous silicon (PS) and polypyrrole (PPy) were prepared in order to study their electrical properties. PS was prepared by electrochemical etching in a HF/Ethanol solution from n-type silicon wafer and PPy by galvanstatic method in a lithium perchlorate/monomer solution. The experimental parameters for preparation of PS and PPy were varied to obtain different morphology of the PS/PPy structures. The surface topography of these structures was analyzed by Atomic Force Morphology (AFM). Tip- and agglomerate-like morphologies of PPy were obtained on PS layers with different pore diameters. The electrical and AFM characterization of PS were studied with and without PPy. Current-voltage (I-V) curves of PS/PPy structures were obtained in dark and under illumination. PS without PPy shows an exponential behavior in the current ((+)Al/n-Si/PS/Cu(-)), but it is almost linear when the PPy layer is deposited over the PS layer ((+)Al/n-Si/PS-PPy/Cu(-)). All structures present photovoltage under illumination conditions. However, this parameter is smaller in Al/n-Si/PS-PPy/Cu structure than Al/n-Si/PS/Cu. The open circuit voltage (VOC) and short circuit current density (JSC) of these structures decrease when the surface morphology of PPy is tip-like, but JSC increase when the surface morphology of PPy is agglomerate-like.