The effects of near ultraviolet (UV) irradiation on water solutions of phenylalanine and tryptophan have been investigated using a broad-band xenon lamp in the region 200–800 nm. This is a step in the laboratory simulation of the effects of Solar radiation on the building blocks of life, specifically α-amino acids, with regards to the origin of life. Results are presented showing the photodegradation of phenylalanine and tryptophan against different UV doses. Some of the degradation products are still protein amino acids. An analysis of the irradiated solutions is carried out by spectroscopic and analytic techniques. The laboratory simulations are discussed in the wake of a life emerging scenario on the primitive Earth.