The international market for green tea is growing. Samples of twenty-five powdered green teas were collected from the market in the United States, and their chemical components were compared. Their prices varied widely, from $4.3 to $160 per 100 g. The higher-priced teas were labeled as “matcha” and are used in the traditional Japanese tea ceremony. They showed a higher content of chlorophyll and of free amino acids (theanine and arginine) than the less expensive teas. They also showed a lower content of epigallocatechin as well as a lower conversion percentage of chlorophyll to pheophytin than those of lower prices. Matcha is traditionally produced in Japan and considered one of the country’s most precious teas. In spite of the large differences in chemical composition compared with the highly priced powdered green teas (ceremonial-grade matcha), the cheaper teas are also labeled as “matcha” in the US market. It is, therefore, necessary to come up with an international definition of matcha to resolve the confusion.