1. The photolysis of p-azidoaniline in organic aprotic solvents was investigated in the absence of O2; the main product of photolysis at room temperature is 4,4′-diaminoazobenzene, but when samples irradiated at 77°K are thawed, the main products are 4,4′-diaminoazobenzene and p-phenylenediamine. The precursor of the end products is p-aminophenylnitrene in the triplet state. 2. In the presence of O2, the main products of the photolysis of p-azidoaniline in aprotic solvents are p-nitroaniline and p-nitrosoaniline. The quantum and chemical yields of their formation were measured. 3. p-Aminophenylnitrene reacts with O2 to form an adduct; subsequently, a dimer is obtained, which breaks down to the end products.