The Achaemenid conquest of the Indus Valley occurred from the 6th to 4th centuries BCE, and saw the Achaemenid Persian Empire take control of regions in the northwestern Indian subcontinent that predominantly comprise the territory of modern-day Pakistan. The first of two main invasions was conducted around 535 BCE by the empire's founder, Cyrus the Great, who annexed the regions west of the Indus River that formed the eastern border of the Achaemenid Empire. Following Cyrus' death, Darius the Great established his dynasty and began to re-conquer former provinces and further expand the empire. Around 518 BCE, Persian armies under Darius crossed the Himalayas into India to initiate a second period of conquest by annexing regions up to the Jhelum River in Punjab.

The first secure epigraphic evidence through the Behistun Inscription gives a date before or around 518 BCE. Achaemenid penetration into the Indian subcontinent occurred in stages, starting from northern parts of the Indus River and moving southward. The Indus Valley was formally incorporated into the Achaemenid Empire as the satrapies of Gandāra, Hindush, and Sattagydia, as mentioned in several Achaemenid-era Persian inscriptions.

Achaemenid rule over the Indus Valley decreased over successive rulers and formally ended around the time of the Macedonian conquest of Persia under Alexander the Great. This gave rise to independent kings such as Porus (ruler of the region between the Jhelum and Chenab rivers), Ambhi (ruler of the region between the Indus and Jhelum rivers with its capital at Taxila) as well as gaṇasaṅghas, or republics, which later confronted Alexander during his Indian campaign around 323 BCE. The Achaemenid Empire set a precedence of governance through the use of satrapies, which was further implemented by Alexander's Macedonian Empire, the Indo-Scythians, and the Kushan Empire.