We report the results of the photoconductivity measurements of the polymer-based diode formed with polymer blend of poly[2-methoxy,5-(2’-ethyl-hexoxy)-1,4-phenylene vinylene] (MEH-PPV) and poly[1,3-propanedioxy-1,4-phenylene-1,2-ethenyllene-(2,5-bis(trimethylsilyl)-1,4-phenylene)-1 ,2-ethenylene-1,4-phenylene] (called B-polymer). The local peak around 2.87 eV in the spectral response of photocurrent indicates the possibility of the excitation from the HOMO level of MEH-PPV to the LUMO level of B-polymer. From these results, we can conclude that the photocurrent and electroluminescence are originated from the rectified microjunction formation in the polymer blend, not from the energy transfer mechanism.