Photochromism of 1,2-bis(2,5-dimethyl-3-thienyl)perfluorocyclopentene (1a) and 1,2-bis(2-methyl-6-nitro-1-benzothiophen-3-yl)perfluorocyclo-pentene (2a) in single-crystalline phases was investigated. Upon irradiation with 366 nm light the colorless crystals of1aand2aturned red and green, respectively. The colored crystals are due to the formation of the closed-ring isomers,1band2b. The colored crystals were bleached by irradiation with visible light. The direction of the electronic transition moment of1bin crystal was estimated from the absorption anisotropy of 535 nm band. When the photogenerated green colored crystal of2awas observed under polarized light, the colored crystal showed dichroism of yellow and blue. The yellow and blue colors were attributed to two perpendicular electronic transitions of2bat 465 and 600 nm, respectively.