The invention relates to the technical field of mounting of immersed tunnels and provides an adjustable balance type component mounting device. The device comprises a bracket beam platform, wherein the upper side of the first end of the bracket beam platform is connected with a steel beam corbel mounting unit; the second end of the bracket beam platform is connected with a simulated steel beam corbel; the first end and the second end are two opposite ends; a plurality of lifting lugs are distributed at the two ends of the bracket beam platform; parts of the lifting lugs are connected with a steel wire rope; the bracket beam platform is connected with a balance hanger. According to the adjustable balance type component mounting device, after the steel beam corbel is mounted, the balance can be adjusted by a chain block and the steel beam corbel is directly hung to a position to be mounted so that the mounting time is saved, and the investment of manpower and machinery is reduced. Furthermore, a worker only needs to screw down or mount a screw or a related connection structure in a mounting process, and the steel beam corbel does not need to be manually transported,, so that the mounting risk is reduced.