The rallies came one week after a Seminole County, Florida, jury returned verdicts finding 29-year-old George Zimmerman not guilty of second-degree murder and manslaughter in the February 2012 death of Martin.
Critics contend Zimmerman, who is white and Hispanic, wrongly suspected Martin, 17, of being a criminal because he was black.
In New York, 2,000 protesters, some carrying “Boycott Florida” signs or wearing T-shirts with Martin’s picture, were led by an emotional Sybrina Fulton, the slain teenager’s mother.
“Trayvon was a child... it made me think they were talking about another man. And it wasn’t,” she said.