A teahouse or tearoom (also tea room) is an establishment which primarily serves tea and other light refreshments. A tea room may be a room set aside in a hotel, especially for serving afternoon tea, or may be an establishment that only serves cream tea. Although the function of a tea room may vary according to the circumstance or country, tea houses often serve as centers of social interaction, like coffee houses.

Some cultures have a variety of distinct tea-centered establishments of different types, depending on the national tea culture. For example, the British or American tea room serves afternoon tea with a variety of small snacks.

Throughout China and Japan, a teahouse (Chinese: 茶館, cháguăn or 茶屋, cháwū; Japanese: chaya (茶屋); Standard Nepali: chiya ghar (चिया घर)) is traditionally a place which offers tea to its customers. People gather at teahouses to chat, socialize and enjoy tea, and young people often meet at teahouses for dates. The Guangdong (Cantonese) style teahouse is particularly famous outside of China, especially in Nepal's Himalayas. These teahouses, called chálou (茶樓) serve dim sum (點心), and these small plates of food are enjoyed alongside tea.

Before tea was used as a social drink, Buddhist monks drank it to aid their meditation. During the Chinese adaptation of Buddhism between 200 C.E. and 850 C.E., tea was introduced as a medicinal herb. It was then evolved to assist Buddhist monks in their meditation by providing the energy needed to stay awake (likely via the effects of caffeine as a stimulant on the brain). Soon after that, tea was popularized as a commonplace beverage, replacing the previously consumed milk- and water-based beverages and Chinese teahouses provided a new kind of social life for the Chinese during the 8th–9th centuries C.E.

According to Japanese cultural tradition, a teahouse ordinarily refers to a private structure designed for holding Japanese tea ceremonies. This structure and specifically the room in it where the tea ceremony takes place is called chashitsu (茶室, literally "tea room"). The architectural space called chashitsu was created for aesthetic and intellectual fulfillment.

During the Edo period, the term "teahouse" came to refer to the place where geisha would entertain their clients or as a place where couples seeking privacy could go.^{[citation needed]} In this case, the establishment was referred to as an ochaya, literally meaning "tea house"; however, these establishments only served tea incidentally. Though the usage of the term chaya for teahouses in the modern sense is now considered archaic—with modern tearooms known as kissaten, serving tea as well as coffee—the term ochaya is still used in Kyoto to refer to the establishments where geisha perform and entertain clients.

In Myanmar, teahouses known as laphetyay saing (လက်ဖက်ရည်ဆိုင်), formerly known as kaka saing (ကာကာဆိုင်), are a staple of urban centers throughout the country. These teahouses, which first emerged during the British colonial era, serve milk tea and a variety of delicacies ranging from native dishes like mohinga to Indian fritters (such as paratha and puri) or Chinese pastries (such as baozi and youtiao). Tea shops have traditionally served as venues akin to conversational salons.

In Pakistan, the prominent Pak Tea House is an intellectual tea–café located in Lahore known as the hub of Progressive Writers' Movement.