'Fresh Prince of Bel Air' Child Actor Floyd Roger Myers Jr. Dead at 42

Floyd Roger Myers Jr. -- a former child actor best known for his role in "The Fresh Prince of Bel-Air" -- has died ... TMZ has learned.

His mom, Renee Trice, tells TMZ ... Myers passed away in the early hours of Wednesday morning from a heart attack at his home in Maryland. She tells us he suffered 3 prior heart attacks over the course of the last three years. She says she just spoke to her son last night.

Floyd kicked off his career as a younger version of Will Smith in the hit sitcom "The Fresh Prince of Bel-Air" ... before taking on the role as a young Marlon Jackson in the television miniseries "The Jacksons: An American Dream."

Myers had a part in one episode of the short-lived TV drama "Young Americans" in 2000.

Floyd was 42.