Abstract: Taking adult tea plantations of Zijuan planted at 900, 1 200, 1 500, 1 800 and 2 300 m as the research object, the change law of main biochemical components of tea variety Zijuan with altitude were analyzed. The results showed that the contents of water extract and tea polyphenols decreased with the increase of altitude in the planting area of altitude of 900~2 300 m, and the highest values were 51.5% and 30.3% in the planting area of altitude of 900 m, respectively. With the increase of altitude, the content of the amino acid increased twice. In the planting area of altitude of 2 300 m, the amino acid content significantly increased to 3.8%. With the increase of planting altitude, caffeine content firstly decreased and then increased, and the highest content was 4.3% in the planting area at 900 m altitude. The total content of catechins firstly decreased and then increased with the increase of altitude, and reached the highest content of 15.88% at 900 m altitude. The anthocyanin content increased gradually with the altitude from 900 m to 1 800 m, the maximum anthocyanin content was 18.5 mg/g at 1 800 m altitude, and the minimum anthocyanin content was 14.3 mg/g at 2 300 m altitude.

Key words: altitude, tea tree variety Zijuan, biochemical components, change law