The significant advantage of LED fill light is that it can be intelligently adjusted according to the photosynthetic characteristics, morphological integrity, quality and yield of different plants. Different types of crops and different crops have different requirements for light quality, light intensity and photoperiod. This requires further development and improvement of light formula research, forming a huge database of light formulas, combined with the development of professional lamps. The greatest value of LED fill light in agricultural applications, thus saving energy, improving production efficiency and economic benefits. LED fill light has shown strong vitality in the application of facilities and gardening, but the price of LED fill light is relatively high, and the one-time investment is large. The requirements for fill light of various crops under different environmental conditions are not clear, the fill spectrum, Intensity and fill light time are not reasonable, which will inevitably lead to various problems when applying the fill light. However, with the advancement and improvement of technology and the reduction of the production cost of LED fill light, LED fill light will be more widely used in facility gardening. At the same time, the development of LED fill light technology system and the combination of new energy will enable the rapid development of factory agriculture, family agriculture, urban agriculture and space agriculture to meet the demand for horticultural crops in special circumstances.