Tajikistan (ⁱ/tɑːˈdʒiːkɨstɑːn/, /təˈdʒiːkɨstæn/, or /tæˈdʒiːkiːstæn/; Тоҷикистон [ˈtɔjikɪsˈtɔn]), officially the Republic of Tajikistan (Tajik: Ҷумҳурии Тоҷикистон, Cumhuriyi Tocikiston; Persian: جمهوری تاجیکستان‎ Jomhuri-ye Tajikestan; Russian: Республика Таджикистан, Respublika Tadzhikistan), is a mountainous landlocked country in Central Asia. It borders Afghanistan to the south, Uzbekistan to the west, Kyrgyzstan to the north, and China to the east. Gilgit Baltistan as well as Khyber Pakhtunkhwa of Pakistan are separated from Tajikistan by the narrow Wakhan Corridor of Afghanistan in the south.

Most of Tajikistan's population belongs to the Persian-speaking Tajik ethnic group, who share language, culture and history with Afghanistan and Iran. Once part of the Samanid Empire, Tajikistan became a constituent republic of the Soviet Union in the 20th century, known as the Tajik Soviet Socialist Republic (Tajik SSR). Mountains cover over 90% of this Central Asian republic.

After independence, Tajikistan suffered from a devastating civil war which lasted from 1992 to 1997. Since the end of the war, newly established political stability and foreign aid have allowed the country's economy to grow. Trade in commodities such as cotton, aluminium and uranium has contributed greatly to this steady improvement.