A self-anchored suspension bridge with composite beam includes a construction ground, a transverse positioning device of the equipment fixed on the construction ground, A cushion laying device fixed on the construction ground and an earth-excavating caisson device fixed on the construction ground are disclosed. The lateral positioning device of the equipment comprises a construction foundation pitfixed on the construction ground with an opening upward. Twenty-four device bodies are arranged on the bottom surface of the lower side of the construction foundation pit in a circumferential array.Open caisson construction is an important step in the construction of composite beam self-anchored suspension bridge, the quality of construction is closely related to the construction of open caisson, In the construction of open caisson, there are often uneven settlement or cracks caused by slight inclination of open caisson. In order to solve the above problems, a self-anchored suspension bridgewith composite beam is designed, which is simple in structure, exquisite in design, convenient in construction and installation, and can realize high quality and high efficiency construction of opencaisson.