A systematic review of the latest research advances in DED technology was provided, focusing on four key developmental directions: multi-heat source hybridization, material supply innovation, energy field regulation, and AI-driven processes. Regarding multi-heat source hybridization, combined processes, such as laser-arc hybridization, the complementary mechanism between different heat sources were leveraged, effectively balancing processing efficiency and forming accuracy. Regarding material supply innovation, novel feeding approaches, including twisted wire, multi-wire, and wire-powder synergistic feeding, had significantly expanded the capability to fabricate functional gradient materials and multi-principal element alloys. It laid the material foundation for enhancing the performance of components overall. Regarding energy field regulation, several methods such as pulse modulation, path planning, and multi-physical field coupling achieved precise control over molten pool dynamics and microstructural evolution. Regarding AI driving, the integration of machine learning and other data-driven techniques expedited the intelligent evolution of DED technology in areas such as processing parameter optimization, intelligent defect diagnosis, and digital twin system development.