*

The fine control of magnetism in topological magnetic materials is crucial since the interplay between magnetism and band topology can lead to exotic emergent phenomena, such as quantum anomalous Hall effect, etc. We present a continuous control of the interlayer magnetic coupling in the newly-discovered intrinsic topological insulator MnBi₄Te₇ by Sb-doping. Through the transport and thermodynamic measurements, it is revealed how the system evolves from antiferromagnetic to ferromagnetic and then ferrimagnetic. We attribute this evolution to the formation of the Mn/Sb antisite disorder which not only leads to the magnetic dilution effect, but also results in extra Mn2/Mn3 magnetic sublattices which act as a switch for dominant Mn1 sublattice in MnBi₄Te₇ to go from antiferromagnetic to ferromagnetic. Therefore, our work provides a system with continuous tuning of the delicate magnetic energy scales in an intrinsic topological insulator and demonstrates defect control as an efficient strategy toward the magnetic control in the system.