Algimantas Valantinas (born October 29, 1961 in Buknaičiai, Mažeikiai Rayon, Lithuanian SSR) is a Lithuanian judge. He was Attorney general of Lithuania since November 24, 2005 until February 11, 2009.
Algimantas Valantinas graduated from Vilnius University with a degree in law in 1985. He then worked as an investigator, assistant to prosecutor and a prosecutor in Kaišiadorys (1985–1988); prosecutor in Širvintos (1990–1991) and Jonava. He was a judge in Jonava (1994–1999) and Vilnius (2000–2005, from 2010).
Algimantas Valantinas speaks Lithuanian, English and Russian languages. Valantinas is married. Has a son and a daughter.