Abstract: With the diversification of combat objects and the complexity of electromagnetic environment, early warning detection is facing the severe challenge of “invisibility, unidentification and irresistibility”. Application direction and difficulties of big data fusion technology in radar detection, tracking, recognition and anti-jamming are discussed. The feasibility and preliminary application effect of four key technologies, including adaptive target detection technology based on data-driven, multi-target tracking technology based on data cognition, target recognition technology based on data mining and fusion, and anti-jamming technology guided by data knowledge are analyzed. Suggestions for further application and development are put forward, which can provide reference for improving the detection and tracking, jamming confrontation, classification and recognition capabilities of early warning detection equipment systems in complex environment of changeable jamming and high-intensity clutter.