Representatives for both stars confirmed to Us Weekly that the celebrity duo have parted ways, but “remain friends”.
The 24-year-old actress and DiCaprio, 36, were first spotted getting cosy while aboard Steven Spielberg's yacht in Monte Carlo during the Cannes Film Festival in May.
During their whirlwind romance, they were seen together in Venice, Italy, Los Angeles, New York, and Sydney, Australia – where DiCaprio was filming his new movie The Great Gatsby.
Their break-up may come as a surprise to some of the Inception star’s friends, one of whom previously said that his pals had “never seen him like this with a girl”.
The pair started dating just weeks after DiCaprio and model Bar Rafaeli ended their five-year on-off relationship.
Lively and her Gossip Girl co-star Penn Badgley called time on their three-year romance last October.