A kinetic model of a high-pressure, free-radical ethylene polymerization is presented. The model of S. Goto, K. Yamamoto, S. Furui, and M. Sugimoto (J Appl Polym Sci, Appl Polym Symp 1981, 36, 21), developed for several common peroxides, was extended to be applicable for the oxygen initiation also. Small-extent propylene copolymerization, as well as telomerization. with isobutane and propylene, are included into the, overall kinetic scheme. The model is based on a string of elemental continuously stirred Lank reactors and is particularly suited for the tubular low-density polyethylene reactors.