Francis M. "Bud" Mullen, Jr. (born 14 December 1934 in New London, Connecticut) is a former executive assistant director of the Federal Bureau of Investigation (FBI) and former Administrator of the Drug Enforcement Administration (DEA).

He became a police officer in New London, before being appointed as an FBI Special Agent in 1962.

In July 1981, Mullen was designated Acting Administrator of the DEA.

However, it was not until 21 January 1982 that President Ronald Reagan announced his intention to nominate Mullen as DEA Administrator, succeeding Peter Bensinger.

[1] Mullen served in an acting capacity from July 1981 until he was confirmed by the U.S. Senate on 30 September 1983 and sworn in as the DEA's third Administrator on 10 November 1983.