Leandro Arpinati (29 February 1892 – 22 April 1945) was an Italian politician.
Arpinati was born at Civitella di Romagna. Before World War I, he was originally an individualist-anarchist and, together with his friend Benito Mussolini, collaborated with the socialist newspaper La lotta di classe. He was a fervid interventionist as early as August 1914. In those years he moved to Bologna, where he worked in the Italian railroad. In the early 1920 he founded the second Fascio di combattimento in the city.
On 21 November 1920 he was amongst the leader of the squads which took part in the fightings between Fascists and Socialists in Piazza Nettuno and Piazza Maggiore in Bologna (the so-called strage of Palazzo d'Accursio). The following year he became deputy and, after the March to Rome, he was made national vice-secretary of the Partito Nazionale Fascista (PNF). In 1926 he became podestà of Bologna, a position which he left in 1929 to became Undersecretary of the Ministry of Interiors. Arpinati held several positions in the Italian sport world, such as the President of Italian National Olympic Committee (CONI) and of the Federazione Italiana Giuoco Calcio (Italian football federation): he led the reformation of the Serie A championship on national level, and organized the 1934 FIFA World Cup. In 1926 he intervened to strip FC Torino of the national football title after a corruption scandal; as the Bologna team had arrived second behind Torino, Arpinati, being a Bolognese, decided to leave the title unassigned (a feat unparalleled until the 2006 Calciopoli) to avoid accuses of personal interest.
In 1930 the PNF secretary Achille Starace accused Arpinati to be behind the attempt against Mussolini in the Bologna Stadium (31 October 1926). He was therefore charged as enemy of the regime, and confined first in Lipari (1934-1937) and then to home detention near Bologna.
In 1943 Arpinati refused the personal invitation by Mussolini to join the Repubblica di Salò, the German puppet-state created in northern Italy after the Allied conquest of the southern peninsula. He was killed on 22 April 1945 at Argelato, two days after the Allied liberation of Bologna, by a group of partisans.