"We want to let you know that we love you and we're not going to leave you," he said, before breaking into song.
Martin's parents, Tracy Martin and Sybrina Fulton also addressed the crowd during the vigil.
"This is the one-year anniversary of this death, this is a somber day for us," Martin said. "But also it's a day of peace for us, because we know as parents we've done all we can do to make our children's lives right."
"I'd just like to say that I'm the mother of two boys," Fulton said. "I have one son on Earth and one son in heaven. I will continue to fight for my boys as well as your boys and girls."
Trayvon Martin was shot on Feb. 26 2012 at the age of 17, by neighborhood-watch volunteer, George Zimmerman in Orlando, Fla. The perpetrator was not prosecuted at first because he claimed he shot the teen in self defense.