This article concerns the Iraqi government's use, possession, and alleged intention of acquiring more types of weapons of mass destruction (WMD) during the presidency of Saddam Hussein. During his reign of several decades, he was internationally known for his use of chemical weapons in the 1980s against civilians and in the Iran-Iraq War. Following the 1991 Gulf War he also engaged in a decade-long confrontation with the United Nations and its weapons inspectors, which ended in the 2003 invasion by the United States.

The United Nations located and destroyed large quantities of Iraqi WMD throughout the 1990s in spite of persistent Iraqi obstruction. Washington withdrew weapons inspectors in 1998, resulting in Operation Desert Fox, which further degraded Iraq's WMD capability. The United States and the UK, along with other countries and intelligence experts, asserted that Saddam Hussein still possessed large hidden stockpiles of WMD in 2003, and that he must be prevented from building any more. Inspections restarted in 2002 , but hadn't turned up any evidence of ongoing programs when the United States and the "Coalition of the Willing" invaded Iraq and overthrew Saddam Hussein in March 2003.

Great controversy emerged when no such weapons were found, leading to accusations that the United States, its President George W. Bush in particular, had deliberately inflated intelligence or lied about Iraq's weapons in order to justify an invasion of the country. While various leftover weapons components from the 1980s and 1990s have been found, most weapons inspectors now believe that Iraq's chemical weapons program did indeed cease production after 1991. However, the Iraq Survey Group report further stated that Hussein intended to restart his WMD programs when the sanctions were lifted.