Reactions of 1,2,4-triazoline-3,5-dione having fluorescent chromophore (DMEQ-TAD) with 9Z-, 11Z-, 13Z-, and 11Z,13Z-isomers of retinoic acid were studied. Except for the 9Z-isomer, the reactions gave the 7,10-adducts in high selectivity while 9Z-isomer gave only the 5,8,11,14-bis adducts. Interesting self-sensitized photochemical isomerizations of these adducts and the mechanism of the addition reactions ant discussed.