The invention provides a three-section large-diameter bored pile structure, and is suitable for foundation construction of an ultra-large sea-spanning bridge. The three-section large-diameter bored pile structure consists of a concrete pile body, inner side main reinforcements, outer side main reinforcements, stirrups, perforated H-shaped steel cylindrical supports, triangular angle steel cylindrical supports and acoustic pipes; the three-section large-diameter bored pile structure comprises three sections from top to bottom structurally, and different structural styles are employed by the three sections; the upper section and the lower section of the pile structure are each of a double-layer main reinforcement structure, and the middle section of the pile structure is of a single-layer main reinforcement structure; the inner side main reinforcements of the three sections of structures are connected vertically to form an integral reinforcement cage; the integral reinforcement cage is put into a vertical deep hole formed by employing a hole drilling method; and integral concreting is performed to form an integral pile foundation structure. According to the three-section large-diameter bored pile structure provided by the invention, the full-length acoustic pipes are arranged in the pile body, and are used for detecting the pile forming quality of bored pile after construction isfinished; on the basis of meeting the design requirement, the construction and installation efficiency of the reinforcement cage of the pile foundation can be obviously increased; the construction safety of the pile foundation is guaranteed under the complicated sea area environment; and ideal structural reliability is provided.