Results of studies on the reaction of indium with urea in the temperature range 20-750 degrees C are presented. The intermediate products of the reaction were identified and the stages of the formation of indium nitride have been suggested. During studies on formation of gallium nitride with the use of urea we have discovered that biuret (H2NCONHCONH2) plays a substantial role in this process. [S. Podsiadlo, Thermochim Acta, 256 (1995) 367]. As shown in this work, biuret, formed in the course of thermal condensation of urea, is the main nitriding agent in the reaction. We decided to investigate the processes of the reactions of indium with urea to form indium nitride.