The pair enjoyed a low-key dinner date at Craig's Restaurant in West Hollywood on Wednesday night, and were spotted leaving in Harry's car.
After being busted by the paps, Kendall tried to keep her her head down in the passenger seat of the 4x4, but was instantly recognisable.
However, at one time Harry was more interested in Kendall's famous sister, asking Kim out on a date when he appeared on a US radio show last year.
Holding up a poster of Kim in a bikini, he'd stuck a Post-It note with the message: "Call me, maybe? ;)."
He told Us Weekly: "She's so cute and I'm a sucker for nice eyes."
18-year-old Kendall caused controversy earlier this week after revealing a risqué photoshoot for Victoria's Secret swimsuit and lingerie catalogue campaigns.