The invention relates to a composite high-efficiency high-flow servo valve. The technical scheme is as follows: the servo valve consists of a composite flow valve and a composite magnetic control motor, two ends of the composite flow valve are respectively connected with a left haft part and a right half part of the composite magnetic control motor. A first electromagnetic converter [2] and a displacement sensor [44] are concentrically arranged in a left shell [3] from left to right in sequence; a valve core [5] is movably arranged in a valve sleeve [11] that is fixed in a valve body [8]; an angle displacement sensor [37], a second electromagnetic converter [19], a left sliding bearing [35], a gear shaft [28] and a right sliding bearing [29] are concentrically arranged in a right shell [17] from left to right in sequence; one side of the gearing shaft [28] is provided with a rack [31] that is meshed with the gear shaft [28]; and one end of the valve core [5] of the composite flow valve is in contact with an end surface of a first electromagnetic memorial alloy [45], and the other end of the valve core [5] is fixedly connected with a second magnetic control memorial alloy [36]. The servo valve has the characteristics of high frequency response, high reliability, high flow, small volume, small leakage, compact structure and high precision.