High tea (OP, P, FBOP) and low levels of tea (PS, BPS) reached 9 points when storing plant cover in Kim Anh factory. Black tea been stored at temperatures 22-25oC, RH 80-90 percent. The results showed that tea store level OP to the 6th month start covering quality degradation and signs must be handled at the 10th month. Tea P after 10 months of preservation quality of tea has begun to reduce damage and degradation strong, especially the 12th month. Cover is made from the premature degradation of the more than cover the rapidly aging, OP tea degrade faster than P tea. Tea is a senior FBOP degraded fastest, to achIeve good quality of cover maintenance period should not exceed 8 months FBOP. The same maintenance mode, low-level tea slower degradation in PS 12-month period, tea BPS can not be longer than 12 months. If the time is spent on the threshold BPS and the fact that tea is no longer used, processed or blended to back. The cause of the failure of black tea in the preservation process is commodities higher, the quicker degradation, difficult to preserve. Same commodity, the more difficult fields as small tea store. During maintenance of biochemical indicators of high levels of black tea stronger than tea transform low level. Tea causes degradation and damage is caused by a combination of many elements within the processing of tea as not achieving good quality tea, high humidity and external factors such as relative humidity higher than 90 maintenance percent, higher than the ambient temperature 27oC.