Organic electroluminescent devices (OLEDs) have the advantages of low energy consumption, high efficiency, high color gamut, etc., and have shown great application prospects in the current display industry. In the current market, organic light-emitting display devices are mainly manufactured by evaporation. In various preparation technologies of OLEDs, inkjet printing can effectively improve material utilization and reduce resource waste compared with current mainstream evaporation methods. However, in the actual operation process of preparing high-quality film by inkjet printing, researchers found that the filming defect of “coffee ring” effect often appears on the surface of the film. The existence of such defects not only affects the quality of the film layer and the performance of the device, but also restricts the further development of inkjet printing technology to some extent. In view of the main causes of the “coffee ring” phenomenon, we mainly analyze and summarize the previous research work from the three aspects of suppressing the capillary flow inside the droplet, increasing the Marangoni flow inward and controlling the three-phase line slip. Through the analysis and summary of these research work, we found that the main purpose is to suppress the capillary flow by three ways: firstly, increase the capillary flow resistance, secondly, adjust the evaporation condition of the solution, and also rely on the interaction between particles can achieve the purpose of inhibiting capillary flow; At the same time, there are two mainstream methods to increase the inward Marangoni flow, one is to optimize the Marangoni flow by changing the solvent composition to change the surface tension of the droplets, and the other is to increase the surfactant Marangoni stream by adding surfactants; For the control of three-phase line slip, we have summarized three methods by analyzing previous studies. One is to use electrowetting to treat droplets, the other is to change the viscous effect between particles and the substrate, and the three-phase line slip is controlled by surface treatment of the substrate. Finally, based on the above series of optimizations and improvements, under the continuous efforts of researchers, the uniform control of inkjet printing films has been basically achieved.