Mario Andrés Meoni was born in 1965 in a road camp in Ascensión, a small town in General Arenales Partido in northern Buenos Aires Province.

[3] In 1999 Meoni was elected to the Buenos Aires Province Chamber of Deputies in the UCR list, representing the fourth electoral district; he was the parliamentary bloc's vice president.

[citation needed] Ahead of the 2007 general election, Meoni left the ranks of the UCR and joined the dissident "Radicales K" who supported the Kirchnerist government and the presidential candidacy of Cristina Fernández de Kirchner; thus he ran for re-election in the provincial list of the Plural Consensus coalition.

[8] Following the 2008 conflict between the government and farmers, in 2010 Meoni joined other radicales K who followed Vice President Julio Cobos in abandoning the Plural Consensus front and petitioning the UCR to allow them back into the party.

[10] Meoni ran for a third term in 2011, this time forming part of Unión Social para el Desarrollo (UDESO), the electoral alliance that backed the presidential candidacy of Ricardo Alfonsín.

[17][18] Just before 10 p.m. on 23 April 2021, Meoni died when his Ford Mondeo lost control and overturned on Route 7 near San Andrés de Giles, a town in Buenos Aires Province.