Tests on propane pyrolysis in a two-sectioned flow reactor have shown that the introduction of ethylene into the feed mixture leads to an increase in the propylene yield. Under certain conditions, the ethylene content in the mixture at the inlet and outlet of the reactor remains constant. At high temperatures, the process can be accompanied by the formation of tarry products. The absence of oxygen-containing byproducts makes the cocracking of propane and ethylene more attractive than the oxidative pyrolysis of propane.