Abstract: The survey among 38 scenic sites of 11 cities and counties in Guangxi demonstrates that there is positive correlation between the air anion concentration above ground and the amount of the plants,especially the trees.The air anion concentration in the mountain forests is higher than that in the flat ground areas;in the rural areas higher than in the urban areas;in high buildings higher than in low buildings;when with breezes higher than with no wind;in places with plants higher than without plants;in fields higher than at seashores;and the highest concentration is at waterfalls.Normally,the anion concentration in soil-ground mountain forests is 1 000～2 000 anions/cm₃,stone-ground mountain forests less than 1 000 anions/cm₃,field 500～800 anions/cm₃,seashores about 500 anions/cm₃,cities 300～600 anions/cm₃,and nearby waterfalls over 10~4 anions/cm₃.