We describe a novel procedure for fabricating conductive patterns on polyvinylidene fluoride (PVDF) substrates using KrF excimer laser treatment. Based on the etching defects which act active centre for conducting layer, the outline of the patterns formed by etching lines is created on PVDF surfaces via a 248 nm excimer laser directwriting optical system; the semiconducting layer can be induced along the selective direction, so that various patterned conductive surface is obtained via 248 nm laser irradiation. The results show that the etching defects not only play the active centres but also effectively separate the conducting layer; using the mask to limit the area of laser irradiation so that it controls the outline of conducting layer. Formation mechanism for conducting layer is proposed by the SEM results at different positions of conducting layer along its spreading direction. The paper will be possible to provide guidance for the conducting PVDF based electronic devices, and patterning other conducting polymer by laser techniques.