The change of water content, mildew of Liupao tea at 35 ℃, 30 ℃, 25 ℃ and humidity of 90%, 80% and 70% were studied. The influence of temperature and humidity on water content and mildew of Liupao tea was analyzed, and the temperature and humidity conditions of Liupao tea were determined. The parameters of spore counting method applied to Liupao tea were optimized and the feasibility of spore counting method in predicting the mildew degree of Liupao tea was evaluated. The results showed that temperature below 25 ℃ and humidity below 70% were the best storage conditions for Liupao tea to prevent mildew. The increase level of spore number and the degree of mildew were synchronized. This method was feasible for rapid assessment of mildew of Liupao tea, and the critical value of the number of spores with mildew was preliminarily determined to be 30.00×107 ·g–1. The results of this study could provide a theoretical basis for the safe storage conditions of Liupao tea, and a new method for rapid assessment of its mildew degree.