The protesters marched from the outskirts of the city to the Chiaiano metro station, where a 15-year-old boy was attacked last week and had to have his spleen removed as a result of his injuries.
“We are all Gaetano,” read one banner, referring to the young victim.
“Gomorra is not to blame, the State is to blame,” read another, referring to the hit Italian television series about the Neapolitan Camorra mafia inspired by Roberto Saviano’s best-selling book.
Some critics argue that the series glamorises organised crime and violence, encouraging young viewers to imitate what they see on the screen.
The protest comes after Italian Interior Minister Marco Minnitti visited Naples on Tuesday to discuss the issue of the city’s youth gangs.
Mr Minnitti referred to the so-called “baby gangs” as “a phenomenon that can no longer be tolerated”.
Italian daily Il Giornale reported at least eleven incidents of youth gang violence in the past two months, including the stabbing of a 17-year-old, the mugging of two teens by a gang armed with chains, and the attack on Gaetano.
Mr Minnitti proposed a community-based approach to the epidemic, which he believes cannot be solved simply by sending extra policemen onto the streets of the southern city.