Abstract: Due to China’s energy endowment of rich in coal while poor in oil and gas,it is crucial to develop and ex⁃pand new ways of supplying unconventional oil and gas resources in order to guarantee China’s energy security.Chi⁃na has abundant coal resources,among which oil⁃rich coal is considerate and widely distributed.Oil⁃rich coal is a kind of coal with strong resource attribute and high tar yield(7%-12%).It is rich in breakable weak bond structure.Its ef⁃ficient and clean conversion to extract the potential oil and gas resources is a very promising way of coal utilization.This paper focuses on three mature oil⁃rich coal’s conversion processes:ground fast pyrolysis for oil extraction,under⁃ground in⁃situ pyrolysis for oil extraction,and synergistic conversion of coal and biomass for oil extraction,respectively.From four aspects of the latest progress and challenges,the essential mechanism and research methods,process analysis and optimization,process device development and application,the basic development of each process was elaborated and summarized in detail.Rapid pyrolysis of pulverized coal for oil extraction is characterized by small particle size and high heating rate,therefore it has the advantage of high tar yield,but it also faces the challenges of poor tar quality and difficult gas⁃solid separation.This paper mainly reviewed the establishment and modification of fast pyrolysis ki⁃netic models,process parameter regulation and optimization,as well as the summary and analysis of related process de⁃vices.Underground in⁃situ pyrolysis for oil extraction refers to the new technology that coal is directly heated and pyro⁃lyzed underground without mining,with oil and gas products are transported to the ground through the extraction wells,which has the advantages of small footprint,low mining cost,and low emission pollution,but it also faces the challenges of non⁃homogeneity of the reservoir,large loss of the product in the long transport path,high formation stress,and high pore pressure.This paper provided a comprehensive summary from the thermodynamic characterization of underground in⁃situ pyrolysis,process enhancement investigation,simulation experimental device development and construction.Coal and biomass synergistic thermal conversion can coordinate the limitations of coal and biomass as carbon⁃based py⁃rolysis feedstocks,realize carbon and hydrogen complementary,achieving pyrolysis scale production while improving volatile fraction yield.However,the synergistic pyrolysis still faces challenges such as the difficulty of product orienta⁃tion regulation,the unclear mechanism of solid⁃phase product structure evolution,and the difficulty of homogene⁃ous mixing of materials in the reactor.This paper summarized in detail the mechanism of interaction between coal and biomass in synergistic pyrolysis,the mechanism of solid⁃phase product structure and utilization technologies,and the development and evaluation of series⁃scale devices.In addition,this paper also briefly introduced the charac⁃teristics and development status of other branch technologies for the efficient conversion of oil⁃rich coal,including mi⁃crobiological conversion,direct oil production and indirect oil production.As an emerging oil and gas alternative re⁃source with rich reserves,clarifying the characteristics of its main oil extraction processes can provide a strong theoreti⁃cal guidance for its rational and efficient utilization,providing more choices for China’s future energy development path.