Abstract: Quenching and partitioning (Q&P) steel, as a representative of the third-generation advanced high-strength steels (AHSS), significantly enhances the strength and toughness of the steel based on traditional high-strength steels through the quenching and partitioning process. The principle, process and technological development of the Q&P process were reviewed, the crucial role of the stability of retained austenite in performance regulation was revealed by analyzing the partitioning of carbon and the laws of microstructure evolution. Meanwhile, the challenges of Q&P steel faced in practical applications, such as springback, Lüders band, and hydrogen embrittlement were discussed in detail, and optimized solutions were proposed. Finally, the future development direction of Q&P steel was summarized, including research on micro-deformation mechanisms and optimization of green processes, aiming to provide theoretical support and technical references for its engineering applications in automotive and other fields.