The Miami franchise, who will compete in Major League Soccer from next season, have regularly been linked with a move for the 32-year-old in recent months.
Kaka, currently in his second stint with Serie A giants Milan, moved to San Siro on a two-year contract in September after a spell at Real Madrid.
With his future at the club uncertain, Orlando confirmed their intention to sign him ahead of their MLS bow.
"Orlando City Soccer Club is in advanced discussions with Kaka," read a statement on their official website.
"Pending completion of the potential player agreement, Kaka would join Orlando City SC in January 2015 prior to the club’s first season in Major League Soccer."
Kaka is widely regarded as one of the finest players Brazil has produced in recent decades - playing regularly for his country for over 10 years.
During his Brazil career, he lifted the FIFA World Cup in 2002 as he added international honours to a host of domestic silverware.
He is the second high-profile signing by a soon-to-be MLS club in quick succession after Spain international David Villa was snapped up by New York City as their first acquisition.
