Bubble tea (also known as pearl milk tea, bubble milk tea, tapioca milk tea, boba tea, or boba; Chinese: 珍珠奶茶; pinyin: zhēnzhū nǎichá, 波霸奶茶; bōbà nǎichá) is a tea-based drink most often containing chewy tapioca balls, milk, and flavoring. It originated in Taiwan in the 1980s and spread to other countries where there is a large East Asian diaspora population.

Bubble tea is most commonly made with tapioca pearls (also known as "boba" or "balls"), but it can be made with other toppings as well, such as grass jelly, aloe vera, red bean, and popping boba. It has many varieties and flavors, but the two most popular varieties are pearl black milk tea and pearl green milk tea ("pearl" for the tapioca balls at the bottom)

There are ongoing debates over the drink's impact on health. While the drink most often contains green or black tea, which offers many health benefits, it also has a high sugar and caloric content, which could exacerbate chronic diseases when consumed daily.

Bubble teas fall under two categories: teas without milk and milk teas. Both varieties come with a choice of black, green, or oolong tea as the base. Milk teas usually include powdered or fresh milk, but may also use condensed milk, almond milk, soy milk, or coconut milk.

The oldest known bubble tea drink consisted of a mixture of hot Taiwanese black tea, tapioca pearls (Chinese: 粉圓; pinyin: fěn yuán; Pe̍h-ōe-jī: hún-îⁿ), condensed milk, and syrup (Chinese: 糖漿; pinyin: táng jiāng) or honey. Bubble tea is most commonly served cold. The tapioca pearls that give bubble tea its name were originally made from the starch of the cassava. Larger pearls (Chinese: 珍珠; pinyin: zhēn zhū) quickly replaced these. The alternative name "boba" (Chinese: 波霸; pinyin: bō bà; Jyutping: bo1 baa3), common in the United States but rare in Asia, originates from a nickname for Hong Kong actress Amy Yip.

There are select cafés that specialize in bubble tea production. Some of the largest global bubble tea chains include Chatime, CoCo Fresh Tea & Juice, Gong Cha, and Kung Fu Tea.

Bubble tea comes in many variations, which usually consist of black tea, green tea, oolong tea, and sometimes white tea. Another variation, yuenyeung, (Chinese: 鴛鴦, named after the Mandarin duck) originated in Hong Kong and consists of black tea, coffee, and milk.

Other varieties of the drink include blended tea drinks. These variations are often either blended using ice cream or are smoothies that contain both tea and fruit.