Taitung County is a county in eastern Taiwan. While its name means "Eastern Taiwan", it is also known as "Houshan" (Chinese: 後山; pinyin: hòushān; Pe̍h-ōe-jī: āu-soaⁿ) by many of the locals, meaning behind the mountains or the back mountains. Taitung is officially administered as a county of the Republic of China.

Taitung runs along the south east coast of Taiwan. Taitung county, possessing 3,515 km² is the 3rd largest county in Taiwan. Taitung County's coastline is 231 km long. Taitung currently has a population of 231,863. The country possess only one registered city, Taitung City. The rest of the county is composed of two towns and thirteen villages.

Due in part to its remote location and isolation by mountains from Taiwan's main population centers, Taitung was the last part of the island to be colonized by Han Chinese immigrants (late 19th century). Throughout the 20th century Taitung remained an economic backwater. Sparsely populated even today, this isolation may have been a blessing in disguise, as Taitung mostly escaped the urbanization and pollution that have come to plague much of the island's lowland areas.