Abstract: A device for the accelerated photo-aging of materials containing polymers, enables samples of the materials to be submitted to the simultaneous action of ultraviolet radiation, temperature and oxygen in an aqueous or gaseous phase with a view to being able to analyze and interpret the phenomena of photodegradation. An external enclosure contains at least four sources of ultraviolet radiation evenly distributed at its periphery and at least one cylindrical wall which is transparent to radiations of at least equal to 295.+-.5 nm and which is coaxial to the external enclosure. A sample holder is arranged coaxially to the vat and moved uniformly in rotation around its vertical axis. Devices are also provided for circulating an aqueous phase inside the cylindrical vat, for regulation of the temperature of the aqueous phase, for ensuring the saturation in oxygen of the aqueous phase, for circulating a gaseous phase inside the external enclosure, and for regulating the temperature of the exposed samples.