Green tea does contain caffeine and, in some cases, contains more caffeine than the same amount of black tea. Even decaffeinated green tea contains a small amount of caffeine.
Although the amount of caffeine in green tea varies depending on the brand of tea chosen, green tea contains anywhere from 11 to 61 mg of caffeine per eight ounces of liquid. The caffeine content is still far below that of coffee, which typically contains 95 to 200 mg of caffeine per eight-ounce cup. Green tea's caffeine content is roughly comparable to that of black tea, which contains 14 to 61 mg of caffeine per eight ounces.