In this study, we evaluated the anti-oxidant activity of a blended health tea and its 8 constituent tea leaves including rooibos tea (Aspalathus linearis), black soybean tea, brown rice tea, Salacia reticulata, Pu-erh tea, Tu-chung tea (Eucommia ulmoides, Oliv), dandelion tea and Snow-tea (Thamnolia vermicularis Ach.) by measuring ORAC and DPPH radical scavenging assay and total polyphenol content. Pu-erh tea showed the highest anti-oxidant activity among all of the tea leaves in all three evaluation methods. Dandelion tea, Tuchung tea, rooibos tea and the blended health tea also showed anti-oxidant activities. We also measured the inhibition activities of the carbohydrate-hydrolyzing enzymes, α-amylase and α-glucosidase (maltase and sucrase) demonstrated by the blended health tea and its 8 constituent tea leaves in vitro. Pu-erh tea, Salacia reticulata and the blended health tea tended to inhibit maltase. On the other hand, no tea leaves inhibited α-amylase or sucrase.