The micro-displacement technology using visual micro-model to simulate real reservoir rock pores has shown extraordinary application value and development potential in recent years. Compared with the traditional macroscopic core flooding experiment，this method shows many advantages，especially the visualization of multiphase flow in pores，which enables researchers to study the microscopic mechanism of oil displacement process. Nano-oil displacement technology has been widely concerned and applied in tertiary oil recovery in recent years. The unique physical and chemical properties brought by the small size of nanoparticles make them play a role in various mechanisms in rock pores. Combing the microscopic nano-oil displacement experiments carried out by many scholars using microfluidic equipment in recent years，the microscopic mechanism of nano-oil displacement mainly includes：wettability change，reduction of interfacial tension（IFT），improvement of mobility ratio，and stabilization of asphaltene. At the same time，the main control parameters affecting the effect of nano-oil displacement were summarized. With the development and improvement of related technologies，the application of microfluidic methods provided a more advantageous platform for the exploration of the microscopic mechanism of nano-oil displacement and optimization of control parameters.