Abstract: Based on the definition of coal mine informatization, the characteristics, typical problems and their representative solutions in different stages of coal mine informatization construction are reviewed, which include single machine(system) automation, integrated automation, mine Internet of things, intelligent mine and perception mine. It is pointed out that: Single machine(system) automation mine, which only carries on simple control to a single device or system, belongs to the initial stage of coal mine informatization construction; Integrated automation mine, which realizes automatic control among multi systems and solves information island, belongs to the middle stage; Internet of things mine, intelligent mine and perception mine belong to the senior stage, in which Internet of things mine and intelligent mine separately realize connection and deep connection of person-person, person-object and object-object, and perception mine realizes cognition and knowledge integration of mine information and status. Relationships among coal mine informatization, digitization, virtualization and intelligence are combed. It is pointed out that: Coal mine informatization includes all contents of mine digitization, virtualization and intelligence; Physical mine, digital mine and virtual mine form an integral closed polygon through object integration, data integration and semantics integration, while smart mine is the core of the closed polygon. Main problems existed in current coal mine informatization construction are analyzed from aspects of perception layer, network layer, platform layer and application layer. Future development trends of coal mine informationzation technology are discussed, which are a large amount of autonomous devices, coal mine transparency and precise control, coordination of edge computing and cloud platform, and a large amount of intelligent APP.