The research progress of microarc oxidation process to tailor hierarchical micro-nano pores is reviewed from the views of scientific mechanism, influencing factors, control strategies and design preparation of functional ceramic coatings. Based on the nature and formation mechanism of micro-nano pores, the classification and characterization methods of micro- nano pore structures are described. After reviewing the influence of electrolyte composition, power supply mode and electrical parameters on the size, shape and distribution of micro-nano pores, the strategies on how to tailor hierarchical micro-nano pores are proposed from the aspects of construction, reduction (or even elimination) and utilization of micro-nano pores. Furthermore, how to construct special functional coatings suitable for different service environments is further discussed. Finally, the latest process exploration for tailoring the micro-nano pore structure and possible developing trends is presented.