Physicochemical properties of trimmed old leaves from tea trees were analyzed in comparison with normal and older large-leaf sun-dried tea (Camellia sinesis Var. assamica). Moreover， water extract was prepared from trimmed old tea leaves， which was then inoculated with Aspergillus tubingensis for theabrownin (TB) production via submerged fermentation. Results showed that there was little difference in nutritional components between normal and older large-leaf sun-dried tea. However， contents of water-soluble polysaccharides， amino acids， protein， total polyphenols， total flavonoids， catechins， theaflavins， thearubigins and TB of trimmed old tea leaves were significantly lower than those of normal and older large-leaf sun-dried tea (P<0.05). In contrast， its total water-soluble carbohydrates were significantly higher than that of normal and older large-leaf sun-dried tea. The optimum condition for TB production from water extract of trimmed old tea leaves by A. tubingensis was as follows: mass concentration of water extract 10 g/L， temperature 40 ℃， shaking speed 150 r/min. Under this condition， TB concentration reached 5.78 g/L， production rate 0.026 g/L·h， and yield 3.922 g/g. This study can provide basis for comprehensive utilization of trimmed old tea leaves and reducing production cost of TB.