An aerial-fog culture method and an aerial-fog culture system for a plant are provided. The aerial-fog culture method includes steps of: (A) conveying a nutrient fluid through a magnetic field of 3000-5000GS to magnetize the nutrient fluid (B) using ultrasonic wave of 1.7MHz-2.4MHz to atomize the nutrient fluid to form an ultrasonic nutrient fluid aerial fog and (C) finally conveying the ultrasonic nutrient fluid aerial fog to the surroundings of a root system of the plant to be absorbed by the root system. The aerial-fog culture method and the aerial-fog culture system for the plant provide advantages of forming less scaling on tube wall or devices, promoting absorption speed and absorbability of the nutrient by the plant, and reducing pests and diseases of the cultivated plants. The invention is to be part of a greenhouse soilless culture technical field, and in particular relates to an aerial-fog culture method and an aerial-fog system for the plant. With the development of modern agricultural technology, the "soilless culture techniques" that are applied in various countries for cultivating plants such as pollution-free vegetable or flowers can be generally defined into two categories, an organic matrix culture technique and an inorganic matrix culture technique. The aerial-fog culture, which is to be part of the inorganic matrix culture technique, applies an atomizing device to atomize the nutrient fluid into fog droplets for directly injecting to the root systems of plants, thereby forming a soilless culture technique for providing water and nutrient for plant growth. In particular, the aerial-fog culture is a high technology agricultural technique which utilizes an artificial created plant root system environment to replace soil environment and does not apply soil or matrix, thereby effectively solving serious contradicts on provisions of water, air and nutrients in conventional soil cultures and enabling crop root systems of cultivated plants to be situated
