Pío Collivadino (August 20, 1869 – August 26, 1945) was an Argentine painter of the post-impressionist school.

Pío Collivadino was born in Buenos Aires, in 1869. He studied drawing at the Italian Argentine cultural society, the Societá Nazionale de Buenos Aires, and in 1889, he traveled to Rome, where in 1891 he was accepted into the Accademia di San Luca, the National Academy of Fine Arts. There, he was mentored by Cesare Mariani, and collaborated in decorative frescoes in the Constitutional Court of Italy.

He returned to Argentina in 1896 and became known for his romanticist lithographs. Colllivadino attended three international festivals in Venice, from 1903 to 1907, where his La hora del reposo (Workday Break, 1903), also known as La hora del almuerzo (Lunch break time) earned a gold medal. He was also at the 1904 Louisiana Purchase Exposition, in St. Louis, where he earned a silver and a gold medal.

These successes encouraged him to transition to Post-impressionism, a genre which had not yet found favor among Argentine art patrons, and he joined the Nexus Group in 1907. The group, led by painters Fernando Fader and Martín Malharro, and sculptor Rogelio Yrurtia, braved initial ostracism and helped popularize the genre locally. Honored with the Order of the Crown of Italy in 1905, Collivadino became an honorary member of the Accademia di Brera, in Milan.