A benzene selective hydrogenation reaction system, comprising a benzene refiner, a first hydrogenation reactor, a second hydrogenation reactor and a separator which are connected in sequence; wherein, a discharge port is disposed at a bottom of the benzene refiner, the first hydrogenation reactor is provided with a first inlet and a first outlet, and the second hydrogenation reactor is provided with a second inlet and a second outlet; the first inlet is connected to the discharge port of the benzene refiner; the first outlet is connected to the second inlet; the second outlet is connected to the separator for separating a catalyst from a reaction product; a catalyst outlet is disposed at a bottom of the separator, and the catalyst outlet is connected to the first hydrogenation reactor for recycling the catalyst into the first hydrogenation reactor; and two micro-bubble units are respectively disposed in interior of the first hydrogenation reactor and the second hydrogenation reactor, and the micro-bubble units are used for dispersing and breaking hydrogen into micro-bubbles with a micron-scale diameter; characterized in that: wherein each of the micro-bubble units comprises a first micro-bubble generator and a second micro-bubble generator which are arranged up and down, the first micro-bubble generator is connected to a gas guide pipe, a top end of the gas guide pipe extends out of a liquid surface of the first hydrogenation reactor for recovering air, a gas inlet is also disposed on a side wall of the first hydrogenation reactor, one end of the gas inlet extends into the second micro-bubble generator, and a structure of the micro-bubble units in interior of the second hydrogenation reactor is the same as a structure of the micro-bubble units in interior of the first hydrogenation reactor; wherein a support member for supporting each other is disposed between the first micro-bubble generator and the second micro-bubble generator. a discharge port is disposed at a bottom of the benzene refiner, the first hydrogenation reactor is provided with a first inlet and a first outlet, and the second hydrogenation reactor is provided with a second inlet and a second outlet; the first inlet is connected to the discharge port of the benzene refiner; the first outlet is connected to the second inlet; the second outlet is connected to the separator for separating a catalyst from a reaction product; a catalyst outlet is disposed at a bottom of the separator, and the catalyst outlet is connected to the first hydrogenation reactor for recycling the catalyst into the first hydrogenation reactor; and two micro-bubble units are respectively disposed in interior of the first hydrogenation reactor and the second hydrogenation reactor, and the micro-bubble units are used for dispersing and breaking hydrogen into micro-bubbles with a micron-scale diameter; characterized in that: wherein each of the micro-bubble units comprises a first micro-bubble generator and a second micro-bubble generator which are arranged up and down, the first micro-bubble generator is connected to a gas guide pipe, a top end of the gas guide pipe extends out of a liquid surface of the first hydrogenation reactor for recovering air, a gas inlet is also disposed on a side wall of the first hydrogenation reactor, one end of the gas inlet extends into the second micro-bubble generator, and a structure of the micro-bubble units in interior of the second hydrogenation reactor is the same as a structure of the micro-bubble units in interior of the first hydrogenation reactor; wherein a support member for supporting each other is disposed between the first micro-bubble generator and the second micro-bubble generator. wherein each of the micro-bubble units comprises a first micro-bubble generator and a second micro-bubble generator which are arranged up and down, the first micro-bubble generator is connected to a gas guide pipe, a top end of the gas guide pipe extends out of a liquid surface of the first hydrogenation reactor for recovering air, a gas inlet is also disposed on a side wall of the first hydrogenation reactor, one end of the gas inlet extends into the second micro-bubble generator, and a structure of the micro-bubble units in interior of the second hydrogenation reactor is the same as a structure of the micro-bubble units in interior of the first hydrogenation reactor; wherein a support member for supporting each other is disposed between the first micro-bubble generator and the second micro-bubble generator.