The Bactria–Margiana Archaeological Complex (or BMAC, also known as the Oxus civilization) is the modern archaeological designation for a Bronze Age civilisation of Central Asia, dated to ca. 2300–1700 BCE, located in present-day northern Afghanistan, eastern Turkmenistan, southern Uzbekistan and western Tajikistan, centered on the upper Amu Darya (Oxus River). Its sites were discovered and named by the Soviet archaeologist Viktor Sarianidi (1976). Bactria was the Greek name for the area of Bactra (modern Balkh), in what is now northern Afghanistan, and Margiana was the Greek name for the Persian satrapy of Margu, the capital of which was Merv, in modern-day southeastern Turkmenistan.

Sarianidi's excavations from the late 1970s onward revealed numerous monumental structures in many sites, fortified by impressive walls and gates. Reports on the BMAC were mostly confined to Soviet journals, until the last years of the Soviet Union, so the findings were largely unknown to the West until Sarianidi's work began to be translated in the 1990s.