Guilherme Castro Boulos (Portuguese pronunciation: [ɡiˈʎɛɾmi ˈkastɾu ˈbowlus]; born 19 June 1982)[1] is a Brazilian politician, activist[2][3][4] and writer.

[8] In 2020 Boulos was the PSOL nominee for mayor of São Paulo in the 2020 election, qualifying for a second round against PSDB candidate Bruno Covas.

[9] As a member of the Homeless Workers' Movement, Boulos became nationally known in 2003, when he participated in an occupation of Volkswagen's land in São Bernardo do Campo.

[17] He became famous in 2003 when he participated in the coordination of the invasion of a Volkswagen's ground in São Bernardo do Campo.

[18] On 17 January 2017,[19][20] Boulos was arrested on charges of committing judicial disobedience and incitement to violence during the repossession lawsuit of a plot of land in the district of São Mateus.