Sources close to the "Vanderpump Rules" star tell TMZ ... Tom is officially dating Victoria Lee Robinson. We're told Tom and Victoria have been hanging out lately and have been officially dating for about a month or so.

We're also told they're enjoying their time together and seeing where things take them -- so it's not super serious, but it has potential to get there.

Tom's featured Victoria on his Instagram Story a few times recently ... including Wednesday night, when he posted a video and a photo of them at his Schwartz and Sandy's cocktail lounge and restaurant in Los Angeles.

Back in December, Tom and Victoria went to a food festival in L.A. together ... but word was they went as friends. Since then, a romance has clearly blossomed -- 'cause they're bangin'.

Anyhoo, in terms of who this gal is -- Victoria is actually a fashion model ... and she's worked with Ford Modeling Agency.

Like a lot of big-time models in this biz, she's got a history with Leonardo DiCaprio. They were linked back in the summer of 2016 when they were photographed leaving a Justin Bieber tour after-party in NYC, when she was 23. Yeah, right in Leo's wheelhouse.

Now, however, she's with Tom ... who has firmly put the Scandoval behind him.

We've seen Tom leaving bars with random women a few times last year -- in Missouri and Tennessee -- and in September, he denied a rumored fling with singer-songwriter Tii.

With Tom back in Hollywood, though -- and as his reality show starts a new season on TV -- he's left the Midwest behind for now, and linked up with a West Coast model. Good move!