The traditional wisdom of utilizing water in practical olefin synthesis has been viewed as a means to reduce alkane partial pressure and assist in coke removal. However, under such harsh reaction conditions, the potential catalytic role of the water molecule remains unclear. This study explores the intriguing concept that the water molecule, through the selective excitation of molecular vibrations and collisions induced by thermal energy and thermal radiation, could act as a catalyst in homogeneous gaseous propane dehydrogenation. This occurs via the generation of the OH• radicals, resulting in an olefin yield of 37.93%, a single pass propane conversion of 51.14%, and an excellent stability of more than 2000 hours.