In this paper we study the photovoltaic performance of dye-sensitized solar cells (DSCs) with high-electroactive-surface-area buckypaper (BP) counter electrodes (CEs). BP is made of entangled multi-walled carbon nanotubes and has a high electroactive surface area, which is effectively 11.5 times higher than that of Pt. The high surface area of BP causes a high I3- reduction rate at the CEs and suppresses the charge recombination at the anodes. Accordingly, the open-circuit voltage, the filling factor, and the power conversion efficiency of DSCs with BP CEs are enhanced, and these photovoltaic parameters exhibit a better trend with the increase of solar power compared with conventional DSCs with Pt CEs.