Angelicin and some of its derivatives are naturally occuring compounds which show interesting photobiological properties. In this review various aspects of angelicin and its derivatives have been reported. The natural occurrence and the chemical synthesis both of naturally occurring and synthetic angelicins have been reviewed. Photochemical and photophysical properties of angelicins have been considered with particular reference to the capacity to generate active forms of oxygen, photoreactions with nucleic acids, proteins and unsaturated fatty acids. Photobiological effects have been considered: skin phototoxicity, antiproliferative effects, genotoxicity, ability to induce hemolysis in erythrocytes, inactivation of prokaryotic and eukaryotic microorganism and of viruses. The ability of some angelicins to induce photocarcinogenesis has been reviewed as well as in the activity as photochemotherapeutic agents.