Prosecutors have said Zimmerman, 29, racially profiled the 17-year-old Martin as he walked back from a convenience store on Feb. 26, 2012, in the rain, wearing a dark hooded shirt. Zimmerman identifies himself as Hispanic.
The race and ethnicity of the minority chosen for the jury was not immediately available.
Prosecutors and defense attorneys chose the panel of six jurors after almost two weeks of jury selection. In Florida, 12 jurors are required only for criminal trials involving capital cases, when the death penalty is being considered.
Martin's shooting death and the initial decision not to charge Zimmerman led to public outrage and demonstrations around the nation, with some accusing Sanford police of failing to thoroughly investigate the shooting.
The six jurors were culled from a pool of 40 jury candidates who made it into a second round of jury questioning.
Before selecting the jurors Thursday, defense attorney Mark O'Mara explored potential jurors' views on whether they thought sympathy should play a role in deciding a case. Juror B-72, a young Hispanic man, said he wasn't affected by sympathetic people because he's never had many close relationships.
"So when a person might seem sympathetic, to me it's indifferent," he said.
O'Mara also asked the jurors about when they thought self-defense could be used. Juror H-6, a white man in his 30s, said he thought deadly force could be warranted if a person feels danger.
"I feel that if you're somewhere you're supposed to be and allowed to be, you should have the right to defend yourself," he said.
O'Mara met resistance from the judge when he tried to characterize the definition for justifiable use of deadly force.
Prosecutor Bernie de la Rionda objected multiple times during O'Mara's line of questioning, eventually leading to Judge Debra Nelson to twice read what will be the jury instruction once the final jury is selection.
"I don't want either side to give an interpretation on the law," Nelson said.
O'Mara said screening the prospective jurors for any biases or prejudices "is probably as critical if not more critical than the evidence."
"If you bring that into the courtroom, then what we can't get is a fair verdict," he said.