There are two factors on the efficiency of dye-sensitized solar cell (DSSC): one is the amount of dye adsorbed, and the other is contact resistance. In this study, TiO 2 nanoparticles (nano-TiO 2 , about 20nm particle size) were infiltrated between mesoporous TiO 2 (meso-TiO 2 ) particles with about 300nm particle sizes, in order to reduce the contact resistance of TiO 2 electrodes. The infiltrated nano-TiO 2 can facilitate electron transfer between meso-TiO 2 particles by filling the empty volume of DSSC electrodes. As a result, the TiO 2 electrode containing 65wt% of meso-TiO 2 and 35wt% of nano-TiO 2 exhibited the highest performance of DSSC.