Leonardo DiCaprio 's keeping summer hot over in France ...
showing off his beach bod during a yacht trip -- and, his girlfriend got the topless memo too. The actor jumped into the Mediterranean during his sojourn to Cannes ..
. splashing around in the cool, blue water before working on his tan on the ship's massive deck. BTW .
.. Leo's rockin' a man-bun in these pics -- unclear if it's for a role or just a style choice, but either way, Leo's definitely pulling it off.
Meanwhile, Vittoria's right by LD's side ...
decked out in a tiny bikini to combat tan lines -- and, even seems to strip it off completely at one point, holding the thin material over her chest with just her hands. The two weren't just alone on a romantic vacay BTW ..
. they were joined on the yacht by a group of friends -- though, we're sure the ship's big enough for everyone to get a little alone time. Leo and Vittoria are reaching a serious couple milestone .
.. with outlets first linking the two last August -- so, they're right around the big one-year mark.
We've seen them sight-seeing in exotic locales, and there was even speculation the two were engaged floating around in March -- though that ultimately proved not to be the case. Good to see Leo's back in the ocean, too ..
. remember, just a few weeks ago DiCaprio suffered a jellyfish sting -- and, he needed medical attention on his A-list ass! Anyhoo ..
. Leo and Vittoria are still going strong -- and, soaking up every second of summer before it's officially go.