And nowadays the newly-single Titanic star wasted no time to get Blake Lively aboard a yacht in the French Riviera.
The flighty pair put on a very affectionate display, embracing and laughing together. Meanwhile, really nearby, DiCaprio's ex Bar Refaeli made a further solo red carpet appearance on the Cannes Film Festival.
The Israeli model, 25, looked breathtaking as she strutted confidently in a flowing blue gown in front of an army of photographers at the premiere of Mel Gibson's film The Beaver.
But as Miss Refaeli lapped the attention in the glitzy event from the army of flashbulbs, DiCaprio and Miss Lively, 23, were enjoying each other's attention as they lounged around in casual clothing.
Miss Lively wore a cream chiffon mini dress which she paired with matching flat shoes.
The fashionista accessorized with a pink Chanel shoulder bag and tied an environmentally friendly scarf to it in case she got cold later in the day.
Inception star DiCaprio was rather dressed down in jeans as well as a blue shirt, covering his eyes in big dark glasses.
He and Miss Lively had been joined on the boat by Steven Spielberg and his wife Kate Capshaw - but did actually have eyes limited to each other.
A witness who saw the pair in the Hotel du Cap Eden Roc said: ‘She was wearing white and he was in a baseball cap. They walked around the grounds together. It looked like they were a couple.'
DiCaprio split from Sports Illustrated model Miss Refaeli recently after an on-off six-year relationship.
Rumors firstly surfaced that most was not well when he didn't escort her to the Met Gala in New York few weeks ago.