Several typical green tea(including Biluochun and High mountain green tea), oolong tea(including Tieguanyin, Rougui and Shuixian) and black tea(including Zhengshanxiaozhong and Tanyanggongfu) were used as the samples for the evaluation of antioxidant activity. The tea polyphenol content in tea powder extrac-tion was compared with that of tea soup. Then, the radical scavenging activity (ABTS+·and DPPH·scavenging activity) and reducing activity (FRAP assay for reducing ability to ferric iron) of tea soup were measured. The results indicated that green tea powder extraction and soup had the highest tea polyphenols content, followed by oolong tea and black tea, except for Tieguanyin. The radical scavenging activity and reducing activity of green tea soup were the highest, while the antioxidant activity of oolong tea soup was lower than green tea but higher than black tea, except for Tieguanyin. Through correlation analysis, it was found that the antioxidant activity of tea soup was highly correlated to its tea polyphenol content, which may relate to the degree of fermentation of tea during process. Due to the unique kneading process, Tieguanyin had the highest compaction degree, which makes the tea soup had the lowest tea polyphenol content and antioxidant activity. In addition, tea polyphenol content of tea soup was less than tea powder extraction, but still had a strong antioxidant activity. It will play a guiding role in the study of tea soup for human health.%随机选取市售几种典型绿茶（碧螺春、高山绿茶）、乌龙茶（铁观音、肉桂、水仙）及红茶（正山小种、坦洋工夫）作为研究对象，比较各茶种茶粉的水浸提液与沸水冲泡茶叶而得的茶汤中的茶多酚含量；并测定茶汤的自由基清除活性（人工合成自由基DPPH·与ABTS+·的清除活性）和体外还原活性（FRAP法测定其对三价铁的还原力）。试验结果表明，绿茶的茶粉浸提液与冲泡茶汤的茶多酚含量最高，茶汤的自由基清除活性与体外还原活性最强，乌龙茶次之，红茶最弱；这与其多酚含量呈正相关关系；而几种冲泡茶汤中，铁观音茶汤的茶多酚含量最少且体外抗氧化活力最弱，这应是源于茶叶包揉工艺的不同。另外，沸水冲泡茶汤较茶粉浸提液的茶多酚含量少，但仍具有很强的抗氧化活性，以日常沸水短时间冲泡的方式获得的茶汤为研究对象进行研究，对消费者进一步认识饮茶的健康功效具有更直接的指导意义。
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