Jay Z spoke out about the case in a Rap Radar interview posted on YouTube Wednesday.
"I was really angry. I didn't sleep for two days," Jay Z said.
"I was really angry about it, that the thing that we all knew, that there was still a bit of racism in America, but for it to be so blatant," he said.
Zimmerman, a neighborhood watch volunteer, was found not guilty this month of second-degree murder or manslaughter in the February 2012 death of Martin, 17, in Sanford, Fla.
Zimmerman pleaded self-defense, saying he shot Martin after the youth attacked him.
He said he followed Martin because he didn't recognize him as a resident of a gated community in Sanford and there had been burglaries reported in the area.
Zimmerman called 911, but then confronted Martin even though a police dispatcher instructed him to remain in his car.
"If you just ask the question, ask yourself the question, 'Didn't Trayvon have the right to stand his ground?'" Jay Z said.
"He was being chased. He was being chased and fought back. You know, he may have won. That doesn't mean he's a criminal, he won. If you try to attack me and I defend myself, how can I be in the wrong? How is that right? This guy went to get some Skittles and go back and watch the All-Star game. He had plans ... he had no intentions of robbing anyone's home," USA Today quoted the musician as saying in the video.
"We all know it was wrong," Jay Z said, in reference to the verdict.
"It was wrong. This guy's not a professional. First of all, you're not a professional to profile someone. A professional law enforcement officer is taught not to profile. This guy's a novice."