The paper reports the discovery of a quantized anomalous Hall effect (QAHE) in intrinsic magnetic topological insulator MnBi₂Te₄. MnBi₂Te₄ is a layered van der Waals crystal with ferromagnetic layers that couple anti-parallel, making it an antiferromagnet. However, under a moderate magnetic field, all layers align ferromagnetically, leading to the emergence of a quantized anomalous Hall response. This makes MnBi₂Te₄ the first intrinsic magnetic topological insulator to exhibit QAHE. The study uses high-quality MnBi₂Te₄ thin flakes grown by self-flux method and characterized using various techniques, including transport measurements and magnetic field-induced Hall response. The QAHE is observed at temperatures up to 4.5 K, with a transport gap of 21 K, and is robust against disorder and temperature fluctuations. The findings establish MnBi₂Te₄ as an ideal material for exploring various topological phenomena and potential applications in topological electronics.The paper reports the discovery of a quantized anomalous Hall effect (QAHE) in intrinsic magnetic topological insulator MnBi₂Te₄. MnBi₂Te₄ is a layered van der Waals crystal with ferromagnetic layers that couple anti-parallel, making it an antiferromagnet. However, under a moderate magnetic field, all layers align ferromagnetically, leading to the emergence of a quantized anomalous Hall response. This makes MnBi₂Te₄ the first intrinsic magnetic topological insulator to exhibit QAHE. The study uses high-quality MnBi₂Te₄ thin flakes grown by self-flux method and characterized using various techniques, including transport measurements and magnetic field-induced Hall response. The QAHE is observed at temperatures up to 4.5 K, with a transport gap of 21 K, and is robust against disorder and temperature fluctuations. The findings establish MnBi₂Te₄ as an ideal material for exploring various topological phenomena and potential applications in topological electronics.