Guillermo Patricio Kelly (b. Avellaneda, Buenos Aires, Argentina, 1922 - d. Buenos Aires, July 1, 2005) was a politician and activist, the leader of the Nationalist Liberation Alliance (ALN) of Argentina from 1953 to 1955. He led the party to drop its former anti-semitism. Arrested after the military coup in 1955, Kelly escaped and fled the country. He later returned to Argentina and became active again in left-wing politics.
Kelly sought to move the ALN from its antisemitic past. He met with Israel's ambassador to Argentina, Dr. Arie Kubovy, and told him that the ALN had forsworn anti-semitism. In 1954, anti-semitism was dropped from the party platform.
Kelly was arrested for having used a forged passport after the 1955 anti-Perónist Revolución Libertadora, a coup d'état by the military. He escaped and fled the country in 1957. Kelly later turned to left-wing radicalism.
He returned to the country. On 24 August 1983, Kelly was kidnapped and released some hours later. Anibal Gordon, a suspected member of Triple A, a right-wing death squad founded in 1973 by the Peron government, was charged with Kelly's kidnapping and in 1985 convicted of three other murders during the early 1970s.