Based on the investigation of the current development trends of deep-sea mining technologies, and in combination with the analysis of domestic and international literature and patent hotspots, three key technological fields of deep-sea mining were identified:collection, lifting, and surface support. Based on the systematic sorting of the core technologies in different fields, a review on the domestic and international research progress is presented in 10 core technologies, including ore crushing, ore collection, mining vehicle traveling, long-distance vertical pipeline transportation, anti-clogging and emergency escape for lifting pipelines, pump-free mineral transportation, underwater acoustic communication, mineral processing, launch and recovery, as well as heave compensation. A multi-dimensional quantitative assessment was conducted on China's advantages and disadvantages compared to the international level in the overall field of deep-sea mining and the three key technological fields of collection, lifting, and surface support. Comprehensive analysis indicates that at the current stage, the main shortcomings of China's deep-sea mining technologies include the low efficiency of core equipment, insufficient long-term reliability, inadequate understanding of deep-sea environmental disturbance mechanisms, and the lack of integrated coordinated operation in at-sea tests. The global challenges of deep-sea mining technology are mainly manifested in dynamic coordinated control under multi-field coupling, flow assurance and equipment reliability in long-distance vertical transportation, and environmental constraints and plume control. In the future, it is advisable for China to focus on breaking through core technologies, strengthening environmental impact assessment and monitoring, and conducting integrated system at-sea tests, so as to move toward the more systematical, smarter and eco-friendly technology, laying a foundation for China's future participation in deep-sea resource exploitation.