The Taipei Joint Bus System (Chinese: 台北聯營公車) is a bus system that serves the greater metropolitan area of Taipei, Taiwan. It is administered by the Taipei Joint Bus Service Management Center, the Taipei City Traffic Bureau, and the New Taipei City Traffic Bureau (formerly Taipei County Traffic Bureau), and is operated by 15 private agencies. It is composed of two system of Taipei City and New Taipei City, with same numbering and fare system.

The system is jointly operated by 15 individual bus transit agencies, sharing the same fare structure, ticketing process, and route numbering. Although most routes are operated by a single agency, there are routes co-operated by two agencies.

Each bus operating agency participating in the joint alliance formed a committee overseeing a joint-venture management center. Operationally, the stops and waiting areas are shared between the individual operators. While ticketing and fare structures are universal within the alliance, each operator remains sovereign with its own structure, assets, revenue vehicles, and legal liabilities. Financially, all the revenue generated are collected to the management then distributed to operating agencies to meet their individual expenditure needs.

Taipei City (/ˌtaɪˈpeɪ/; [tʰǎipèi]; Chinese: 臺北市 or 台北市; pinyin: Táiběi Shì) is the capital of the Republic of China (Taiwan). Situated at the northern tip of the island of Taiwan, Taipei is located on the Tamsui River; it is about 25 km southwest of Keelung, a port city on the Pacific Ocean. It lies in the two relatively narrow valleys of the Keelung (基隆河) and Xindian (新店溪) rivers, which join to form the Tamsui River along the city's western border. The city proper (Taipei City) is home to an estimated 2,618,772 people. Taipei, New Taipei, and Keelung together form the Taipei metropolitan area with a population of 6,900,273. However, they are administered under different local governing bodies. "Taipei" sometimes refers to the whole metropolitan area, while "Taipei City" refers to the city proper. Taipei City proper is surrounded on all sides by New Taipei.

Taipei is the political, economic, and cultural center of Taiwan. The National Palace Museum which has one of the largest collections of Chinese artifacts and artworks in the world is located in Taipei. Considered to be a global city, Taipei is part of a major industrial area. Railways, high speed rail, highways, airports, and bus lines connect Taipei with all parts of the island. The city is served by two airports – Taipei Songshan and Taiwan Taoyuan.