Disclosed is a method for strengthening and lifting a high-rise building that has a raft foundation, comprising: arranging a plurality of measuring points at intervals around the outer contour of a building, and determining the side to be lifted of the building according to the elevation of the measuring points; distributing a plurality of reinforcement grouting holes perpendicular to a raft foundation at intervals within the range of the raft foundation, and using pressure grouting in the reinforcement grouting holes to form a reinforcement under the raft foundation; laying downwardly inclined lifting holes on the outer side of the raft foundation at two ends close to the side to be lifted of the building; and performing simultaneous pressure grouting in the lifting holes to lift the side to be lifted of the building.