Alejandro Ariel Vilca (born 5 July 1976) is an Argentine activist, garbage worker, trade unionist and politician, active in the Socialist Workers' Party (PTS). A member of the indigenous Qulla people, Vilca was elected to the provincial legislature of Jujuy Province in 2017 on the Workers' Left Front (FIT) list, which won 18% of the vote. In 2021, he was elected to the National Chamber of Deputies.

Vilca was born on 5 July 1976 in San Salvador de Jujuy, capital of Jujuy Province. His family belongs to the Qulla people, one of the many indigenous peoples who inhabit the Argentine Northwest.^[1] Alongside his four siblings, he was raised by a single mother who worked as a domestic maid and janitor at the city's private hospital. Vilca grew up in the San Isidro neighbourhood. Upon finishing high school, he moved to San Juan to study architecture at the National University of San Juan (UNSJ); he worked odd jobs as a mason, a waiter, and an ice cream vendor to sustain himself while he studied.^[2] In the UNSJ he joined En Clave Roja, the Socialist Workers' Party (PTS) student wing which was then in opposition to the education reform of president Carlos Menem.^[3]

From 1996, Vilca became an active member of the PTS, regularly attending protests and picketing organised by the unemployed, teachers and state workers of San Juan. He was forced to drop out of university and return to Jujuy due to economic hardships, and upon his return, he began organising the PTS in his home province. Vilca sought to share the anti-capitalist and socialist ideals he had forged during his time in university.^[4]

Vilca became an employee at the San Salvador municipal government. In 2006, he led a protest alongside the Coordinadora Provincial de Trabajadores en Negro (a provincial trade union for informal sector workers), which grouped teachers and health workers, among other state workers, seeking higher wages and better work conditions. Following that, Vilca and another major activists involved in the protests were transferred to garbage collecting at the Alto Comedero neighbourhood. The protests would eventually pay off, however, as many of those workers were given contracts by the municipal government as they had requested.^[5]

Ahead of the 2011 general election, a number of trotskyist political parties, including the PTS, formed the Workers' Left Front to contest the election. Vilca was nominated as the alliance's candidate for governor of Jujuy: he received 1.93% of the vote. Four years later, in 2015, Vilca was the first candidate in the FIT list to the provincial legislature. He received 7.06% of the vote, nearly enough to be elected.^[6]