Aaron told BlackAmericaWeb.com in an online video published Wednesday that Kaepernick is being blackballed by NFL owners who disagree with his politics.
"I think he's getting a raw deal," Aaron said. "If you look at all the quarterbacks in the league right now, I think you have to say he is 1, 2, 3, 4. I don't think anybody can do the things he could do. I wish somebody would open up and give him a chance to do his thing."
Aaron endured racism throughout his legendary baseball career. The Hall of Famer was the target of racist taunts, death threats and hate mail throughout his historic chase of Babe Ruth's home run record in 1974.
Kaepernick, 29, made headlines last season with the San Francisco 49ers when he kneeled during the national anthem to protest injustices against African Americans and minorities in America. He opted out of his contract in March and became free agent, but no team has signed him for the 2017 season.
In the past couple of weeks before preseason games, a number of NFL players have continued Kaepernick's national anthem protest.
Aaron would like to see more players participating in the protests to support Kaepernick.
"I'd love to see some other players stand up," Aaron told interviewer Roland Martin Aaron after the Braves held a weekend in honor of the baseball great and one-time home run king. "I would love that. I think it would give him some incentive, I think it would help him. The thing that bothers me about this whole situation is he's going to all these camps, I suppose, and nobody seems to think he stands a chance of being No. 1.
"Here is a man, a young player, who almost carried a team to a championship, to a Super Bowl. I remember that. I was a Ravens fan, and he was playing against my team, the Ravens. Be that as it may, somebody needs to give this young man a chance."
Later Wednesday, the NAACP said the organization is seeking a meeting with NFL commissioner Roger Goodell to discuss Kaepernick.
Derrick Johnson, the NAACP's interim president and CEO, said "no player should be victimized and discriminated against because of his exercise of free speech."