Butterfly pea flower tea, commonly known as blue tea, is a caffeine-free herbal tea, or tisane, beverage made from a decoction or infusion of the flower petals or even whole flower of the Clitoria ternatea plant. Clitoria ternatea is also known as butterfly pea, blue pea, Aprajita, Cordofan pea, Blue Tea Flowers or Asian pigeonwings.

Derived from a plant that is common to most South East Asian countries, butterfly pea flower tea has been brewed for centuries but only recently been introduced to tea drinkers outside the indigenous area. Butterfly pea flower tea gains its distinctive tint from the deep blue color of the petals that has made the plant a popular dye for centuries. One of the aspects of the tea is the fact that the liquid changes color based on the pH level of the substance added to it, for instance, adding lemon juice to the tea will turn it purple.