Many studies reported that dye-sensitized solar cells have more significant capacitance characteristics than the silicon solar cell. In this study, it was found the capacitance characteristics of dye-sensitized solar cell changes with the imposed bias voltage. The bias voltage is indispensable in the standard measurement for the conversion efficiency of dye-sensitized solar cell. The influence of changed capacitance during the measurement on the conversion efficiency of dye-sensitized solar cells was investigated. The analysis on the EIS spectra and equivalent circuit shows that the capacitance of dye-sensitized solar cells is small and the deviation cell I-V characteristics from the steady-state value is minor when the applied bias is small; while under a condition with a large applied bias, the capacitance characteristics of dye-sensitized solar cell grew rapidly and the I-V characteristics deviated from the steady-state value significantly increased. This phenomenon is helpful for the accurate measurement of the quantum conversion efficiency and photoelectric conversion efficiency of dye-sensitized solar cells.