The invention relates to a low-carbon ethylbenzene dehydrogenation catalyst, and a preparation method and an application thereof. The invention mainly aims at solving the technical problem of a high reaction initial point temperature caused by low low-temperature activity of low-potassium catalysts in prior arts. The low-carbon ethylbenzene dehydrogenation catalyst is composed of the following components, by weight: 60-80 parts of Fe2O3, 6-15 parts of K2O, 6-15 parts of CeO2, 0.5-4 parts of Mo2O3, 0.5-5 parts of CaO, and 0.1-3 parts of Ga2O3. With the technical scheme, the technical problem is well solved. The method can be used in industrial productions of styrene prepared through ethylbenzene dehydrogenation.