A method for reinforcing and lifting a building based on numerical simulation includes: establishing an initial building model representing a building undergoing settlement, and acquiring an initial settlement displacement of the building; adjusting parameters of a shallow foundation under a building raft foundation based on the initial building model to simulate reinforcement of the shallow foundation and form a post-reinforcement shallow foundation model; adjusting parameters of a deep foundation under the building raft foundation based on the post-reinforcement shallow foundation model to simulate reinforcement of the deep foundation and form a post-reinforcement deep foundation model; and dividing an intermediate lifting layer located between the deep foundation and the shallow foundation into a plurality of lifting zones based on the post-reinforcement deep foundation model, and performing corresponding simulated lifting according to a settlement displacement of each region to achieve simulated lifting of the building.