Taking a super high-rise building as an example, this paper analyzes the determination principles of pile diameter and pile length, characteristic value of vertical compressive bearing capacity of a single pile, and pile arrangement scheme of non-end-bearing piled raft foundation under the core tube. The quick estimation method of pile number under the core tube, and characteristic value of vertical compressive bearing capacity of a single pile is presented at the stage of pile foundation scheme design. Four pile foundation schemes with different pile diameters and different forms of pile arrangement are analyzed and verified by finite element method, and the results show that the quick estimation method is feasible. At the same time, based on the above analysis and optimized design of pile foundation stiffness to reduce differential settlement of pile foundation, the design optimization strategy of reducing the raft thickness and reinforcement under the core tube is put forward.