Lateral photoelectrode-counter electrode structure with microscale interdigital fingers of TiO2/FTO film is constructed for dye-sensitized solar cells by femtosecond laser patterning. A highest photon-to-electron efficiency of 5.18% under AM 1.5G is achieved. A novel tandem DSSC is fabricated with ultracompact structure due to this lateral design, accomplishing 6.21% photon-to-electron efficiency.