Lombard's mother is from Tahiti. Lombard is a naturalized U.S. citizen, but when she was one, her father, who is of Russian, Italian and Swiss descent, took her to Barcelona, Spain. She later attended a number of Swiss boarding schools where she became fluent in Spanish, English, Italian , French, and German. She came to New York when she was 18 and began modeling and taking acting classes.

Lombard was discovered during a Calvin Klein photo shoot with a Native American theme. One of her photographs was chosen to be a billboard ad.

Her theatre training and stage experience primarily comes from New York City's Gallery Theatre, the Neighborhood Playhouse, the Lee Strasberg Theatre Institute and the Actors Studio. Lombard was with controversial director Damian Chapa shortly after his divorce from Natasha Henstridge.

As an actress, she appeared on the first season of The L Word, and also in The 4400. She reprised her role as Marina Ferrer in the first episode of Season Four of The L Word and made one more brief appearance later that season (as an actress auditioning for Jenny's film, Les Girls). Karina Lombard has never come out as lesbian but hinted that she was bisexual. When asked about the love scenes she has done in the L Word she said, "I grew up in Europe and you know - you love who you love, so I didn't have to prepare, you know what I mean?"

Later, in 2006, she did a six-page nude pictorial for Playboy where she portrayed both feminine and masculine counterparts of a lesbian couple. The concept was her own idea. She told planetout.com: "one night I had this dream about these images, and it was all about the dichotomy of male and female within an individual, and the empowerment within a human being in embracing the female and the male inside of you -- the dichotomy of the wild self vs. the tamed self. I woke up and I was like, "Whoa -- what was that about?" And when I get those dreams, it's always very specific, and for a specific reason, it's not random."

Though this comment and the pictorial would seem to confirm her orientation as bisexual, she told the magazine: 'I thought I was bisexual until I did the The L Word, then I associated it with work..."