Gel polymer electrolytes for DSSC were manufactured with different molecular weight polymers and their impedance and photovoltaic performance were measured. PVP-a(Mw 40,000), and PVP-b(Mw 360,000) polymers were used for our study. Impedance spectra showed that PVP-a had lower resistance than PVP-b. But DSSC based on PVP electrolytes had similar efficiency. The efficiencies of DSSC with PVP-a and PVP-b gel polymer electrolyte were 1.5% and 1.6%. The reason of similar efficiency seemed to be the similar penetration behavior of PVP molecules into TiO2 nanoporous.