Khole, 31, called off the relationship with the pro basketball player, reported People magazine.
The "Keeping up with the Kardashians" star and Harden started dating last year. However, their relationship became strained after Khole's estranged husband Lamar Odom's health crisis. Odom was found unconscious at a love ranch after which she remained by his side throughout his time in hospital.
Khole previously said that Harden, 26, had remained supportive as she attended to Odom, saying he had been "very supportive and awesome.