J-aggregate formation in the films of spiropyran derivatives ( SP1822 and SP18) prepared with Langumuir-Blodegett ( LB) and vapor-deposition methods was investigated. In the films of SP1822, J-aggregate formation occurred with UV light illumination and thermal treatment. In the case of SP18 film, on the other hand, only photoisomerization occurred. When the PMC-form of SP18 was transferred onto a glass plate, J-like aggregate formation occurred after UV light illumination. By UV light illumination during evaporation process, SP1822 formed J-aggregate. Finally, SP1822 J-aggregate film oriented one-dimensionally was fabricated by using a PTFE layer as a substrate.