Objective: Analyze the dynamic changes trend of main functional components in Wuniuzao green tea and black tea which are prepared from fresh leaves in summer and explore the intervention effects of Wuniuzao green tea and black tea (in summer) water extract on liver and gut microbiota in obese mice. Methods: Detect the dynamic changes trend of main functional components of samples from each processing procedures in Wuniuzao green tea and black tea (in summer). After acclimation feeding for 1 week， 50 mice were randomly divided into the following groups， such as normal control (NC) group， Wuniuzao green tea (WG) group， Wuniuzao black tea (WB) group， high-fat diet (HFD) group and positive control (PC) group， which were continuously administrated (NC and HFD group were given normal saline， PC group was given atorvastatin (10 mg/kg BW)， WG and WB group were given tea water extract (300 mg/kg BW) for 8 weeks. The changes of body weight， Lee's index， blood glucose levels， serum lipid， pathobiology in liver tissues， SREBP1c signaling pathway in liver lipid metabolism and gut microbiota were measured. Results: During processing procedures， the contents of main functional components of Wuniuzao green tea and black tea (in summer) changed obviously. Compared to the‘Fresh leaves’ sample of Wuniuzao green tea (in summer)， the contents of tea polyphenol and caffeine in the‘Drying’ sample were respectively increased by 3.87% and 0.61%， while the contents of free amino acids， soluble sugar， and soluble protein were respectively reduced by 0.56%， 0.47%， and 4.26%. Compared to the ‘Fresh leaves’ sample of Wuniuzao black tea (in summer)， the contents of tea polyphenol， caffeine， free amino acids， soluble sugar， and soluble protein were respectively reduced by 6.15%， 0.40%， 1.08%， 0.53%， and 4.11%. Compared to the HFD group， the WG group and WB group exhibited a significant difference (P < 0.05) in body weight (27.73 g， 26.78 g) and Lee's index (3.18， 3.15). Besides， tea water extract could also significantly improve blood glucose tolerance levels， serum levels and lipid deposition in liver， and regulate the level of SREBP1c signaling pathway related genes and proteins of liver lipid metabolism in mice. The results of gut microbiota analysis showed that tea water extract decreased the ratio of Firmicutes/Bacteroidetesd (F/B)， and increased the growth of beneficial bacteria， including Rikenellaceae and Alloprevotella. Conclusion: Wuniuzao green tea and black tea (in summer) water extract have obvious effects on intervening abnormal liver metabolism and gut microbiota dysbiosis in obese mice， and the Wuniuzao green tea water extract has a better effect.