In the paper, rhizosphere soils of the 6 Oolong tea plant with different ages were collected, and soil autotoxicity and effects of soil to leaf quality indexes of tea seedlings were measured. The results of soil autotoxicity showed that inhibition rates of soil to tea plant height raise as soil age increased, especially after 9 years, which increased significantly. Analysis results on leaf quality indexes of tea seedling showed that polyphenols, theanine and caffeine contents of the 6 tea leaves raise firstly, then fell as soil age increase, especially over 9 years, which declined significantly. Correlation Analysis results showed that autotoxity was positive with planting years of tea soil, and negative with the 3 quality indexes significantly. In conclusion, soil being planted for several years continuously had autotoxity to tea plant, and especially over 9-year-old soil, it had significant effects on leaf quality of tea seedling.