Photochromic thiophenophan-1-ene-S,S,S',S'-tetraoxides have been synthesized by oxidation of sulfur atoms of thiophenophan-1-enes, and their photochromic properties were studied. The tetraoxides indicated photochromism and the quantum yields for photocyclization reactions became higher than that of nonbridged dithienylethene-S,S,S',S'-tetraoxide due to fixation of conformations.