The incident was recorded with a cellphone and published on social media, leading authorities to arrest a local tattoo artist and his accomplice.
Both confessed, police said.
Tattoo artist Maycon Wesley Carvalho dos Reis, 27, and bricklayer Ronildo Moreira de Araujo, 29, were charged with torture.
In Brazil, torture is considered a heinous crime, and perpetrators cannot be released on bail.
According to local media, they told authorities their intention was to teach the boy and all thieves a lesson.
A crew from Record TV, a CNN affiliate in Brazil, talked to the 17-year-old and his family but didn't name him. Brazilian law prohibits minors to be identified by the press.
"It was like if my son didn't have a family," the mother told the station. "I think that this is what the people who did this were thinking, that he didn't have anyone and that nothing would happen to them."
Volunteers created an Internet fundraising page to help pay for the tattoo removal.
"The tattoo can be removed, but the scars will remain in my mind," the boy said.