Abstract: Compared with the traditional display technology, mini light-emitting diode (mini LED) has the advantages of high brightness, fast response, high contrast, rich color and long service life. Most importantly, because the micron level LED chip is used as the backlight, the backlight of mini LED display screen is more uniform, and can carry out extremely fine backlight area control, which is of great significance for the development of the display market. The development history of mini LED display technology was reviewed and the current commercial research progress of mini LED in backlight and direct display technology was summarized, in order to provide reference and implications for the development and application of mini LED.