The effect on the quantum yield for the cyclization reaction and the circular dichroism (CD) spectral change by the addition of beta-cyclodextrin (beta-CDx) to an aqueous solution of 2,2'-dimethyl-3,3'-(perfluorocyclopentene-1,2-diyl)bis-(benzo[b]thiophene-6-ammonium)iodide (1a) were studied. The quantum yield for the cyclization reaction was increased because of the increase of the ratio of the photoactive anti-parallel conformation. The CD spectral change upon irradiation with 313 nm light was also studied. The induced CD spectrum of an aqueous mixture of 1 and beta-CDx changed from negative to positive by 313 nm light irradiation and the CD spectral change was photoreversible.