MnBi₂Te₄ as an intrinsic magnetic topological insulator has attracted lots of attention. Since the electronic structure of MnBi₂Te₄ is quite sensitive to the change of lattice constant, here in this work, we use a first-principles method based on density functional theory to implement the isometric strain control of the electronic structure of MnBi₂Te₄ antiferromagnetic bulk. The so-called isometric strain is to change the lattice constant under the premise that the volume of the crystal remains unchanged. Our results show that the energy band structure of the system changes sensitively under the action of isometric tension and compression strains of the material, and the system has an insulator-metal phase transition. In particular, when a certain strain is applied, the conduction band and the valence band cross at Γ, and the system presents a zero band gap state. Under this strain, the band inversion can still be observed, showing non-trivial energy band topological properties. According to the charge density and local charge density maps under different strains, it is found that the isometric strain will affect the interlayer spacing of the system's seven-fold layers. The isometric compression and tensile strain can increase and reduce the Te atomic layer spacing respectively, indicating that isometric compression is beneficial to reducing the antiferromagnetic interlayer coupling. Through the control of isometric pressure and strain, we can master the change law of the electronic structure of MnBi₂Te₄, which has important guiding significance for the research of physical properties and experimental preparation of the intrinsic magnetic topological insulator MnBi₂Te₄.