Abstract: Under the industrial backdrop of the “Double Carbon” strategy and the transformation of coal into a raw chemical material, coal resources are becoming increasingly complex and difficult to process. The problem of material refinement in the feed has become prominent, and the low flotation efficiency of fine coal has emerged as a critical technical bottleneck restricting industry development. This paper provides a deep analysis of the mismatch mechanism between fine coal and traditional flotation processes across multiple scales—molecular/nano, micron, and macro. Addressing challenges such as poor floatability, complex surface properties, and significant slime interference, substantial progress has been made in flotation technology, equipment structure, and process flow. At the technical level, flotation reagents have upgraded from traditional non-polar oils to emulsified, compounded, and specialized collectors for low-rank coal; meanwhile, technologies such as micro-nano bubble flotation, clay dispersion and depression, and solution chemistry regulation continue to mature. At the equipment level, large-scale and high-efficiency mechanical agitation, jet-type, and column flotation devices are increasingly sophisticated. Concepts like multi-field coupling and mineralization-separation decoupling have effectively improved mineralization efficiency and separation selectivity. Furthermore, the application of online detection, image recognition, and intelligent control is accelerating the digital and intelligent upgrading of flotation systems. At the process level, the adaptability of direct flotation, desliming flotation, classification flotation, and multi-stage combined processes has significantly improved, effectively enhancing the separation efficiency of complex coal slime. In the future, the refinement of separation scales, the advancement of separation levels, and the scaling-up of processing capacity will become the core themes for fine coal flotation. Overall, the field is moving toward a synergistic development of high-efficiency equipment, green reagents, intelligent control, and adaptive processes, providing vital technical and equipment support for the clean and efficient utilization of low-quality, complex coal resources.