The utility model relates to a butene oxidative dehydrogenation reaction device, and belongs to the field of chemical engineering devices. According to the reaction device, a medium-pressure steam pipeline is divided into two paths, one path is a steam hot line, the other path is a steam cold line, and the steam hot line is communicated with a fourth heat exchanger and is communicated with the steam cold line through the fourth heat exchanger; the steam cold line is sequentially connected with the stop valve, the first distributor and the top end of the first reactor; the stop valve and the steam heater are connected with the steam cold line in parallel; the bottom end of the first reactor is sequentially connected with the first heat exchanger, the second heat exchanger, the second distributor, the heat treatment equipment and the top end of the second reactor through a first reactor generation gas line; the bottom end of the second reactor is communicated with the fourth heat exchanger through a second reactor generation gas line. The reaction device provided by the utility model is simple in structure and scientific and reasonable in design, can improve the reaction selectivityand prolong the operation period of the reactor, and does not cause the loss of a steam enthalpy value.