The irradiation of 1-(veratryl)-2-(3′-methoxyphenoxy)glycerol in alkaline methanol solution was performed in the presence of hydrogen peroxide (UV and visible light) and sensitized by methylene blue (MB) in the presence of O2 (visible light). The photoproducts were analysed by gas chromatography-mass spectrometry (GC-MS). The β-O-4 ether bond cleavage, which usually occurs in reactions involving singlet oxygen, was not operative, since the corresponding phenol 3 was detected in trace amounts only and the carbonyl derivative 4 was not detected at all. Irradiation in the presence of MB/O2 induced the oxidation of the benzyl group into a carbonyl function and produced the hydroxymethylation of one benzene ring of compound 1. In contrast, such reactivity was not observed when 1 was irradiated in the presence of H2O2: nevertheless, hydroxylation of one benzene ring was detected. For both types of irradiation, four stereoisomers were formed. The mass spectrum showed the addition of hydrogen peroxide to the B henzene ring of compound 1. This is the most important reaction, and was ascribed to the radical addition of a superoxide anion assisted by the hydroxyl groups in the β or γ positions of the glycerol moiety.