"I cannot comment on the reason, but can confirm that Ciara and Bow Wow have split," said Tracy Nguyen in a statement Monday. The spokeswoman also took the unusual step of stating that the breakup wasn't amicable.
A message left with Bow Wow's publicist wasn't immediately returned.
Bow Wow, whose real name is Shad Moss, was christened Lil' Bow Wow by Snoop Dog. He dropped the "Lil"' in 2003.
The 19-year-old rapper sang a duet with Ciara on "Like You," the second single off his fourth album, "Wanted."
Ciara, 20, was dubbed "the First Lady of Crunk & B" by Lil' Jon, who produced her debut single, "Goodies," from her 2004 album of the same name.