The use of polymeric materials requires the continuous expansion of the range of peroxide initiators. Silicon-containing peroxides have high thermal stability and are used as high-temperature initiators of polymerization. Nitrogen-containing peroxides are used as low-temperature polymerization initiators. The question of thermal stability is often decisive for the practical application of these compounds. Therefore, the thermolysis of Carbon, Silicon, and Nitrogen-containing organic peroxides was investigated by differential thermal and thermogravimetric analysis.