The photo-irradiation of 3, 4-bis(phenylmethyl)-2(5H)-furanone (5) in acetone or in methanol resulted in selective rearrangement of the 4-phenymethyl moiety and gave 5-phenyl-1-(phenylmethyl)-3-oxabocyclo[3.1.0]hexan-2-one (9)along with cis- and trans-3, 4-bis(phenylmethyl)dihydro-2(3H)-furanone (10a and 10b). The difference in photochemical behavior from that of β-apolignan (1) is discussed.