Van Straten was born Kristin Neubauer in Racine, Wisconsin. She is of German descent. During childhood, she played Sports, rode horses, and fired shot guns. She graduated from The Prairie School in Racine. Van Straten studied fine arts at Washington University in St. Louis as well as in Boston and New York (Parsons The New School for Design) in her youth, but decided to become an Actress and moved to Los Angeles, where she has been living since she began acting in 1994. She continues to draw and paint. Her works include commissioned portraits. Van Straten carries out conservation work to improve the treatment of animals.
In 1995, van Straten had her first regular role in a television series, as Maggie Reynolds on The Crew. Other recurring roles include Geneva Renault in Total Security, Candy Cooper in That's Life, Rebecca Colfax in Dirty Sexy Money, and Belinda Slypich in Hidden Hills. Perhaps her best known film role was in Dancing at the Blue Iguana in 2000. Van Straten played a porn star appearing as the featured act at a Los Angeles strip club and performed an extended nude dance. In 2001, she starred in the award-winning short film Room 302, and in 2004 she had a minor role in the film 50 First Dates, which starred Adam Sandler. In the animated series Justice League, she supplied the voice of the superhero Mera.
From 2008 to its conclusion in 2014, van Straten played the vampire Pamela Swynford De Beaufort on the HBO fantasy drama series True Blood. On December 8, 2009, TV Guide confirmed she had been promoted from recurring status to a series regular. In 2011, van Straten was cast in the fantasy television series Once Upon a Time as the evil fairy Maleficent (the wicked fairy godmother, using the name from Disney's Sleeping Beauty), the rival of the Evil Queen of Snow White.
In 2011, van Straten teamed with the Animal Legal Defense Fund in an unsuccessful fight to release Tony, a Siberian-Bengal tiger who has been kept as a roadside attraction at the Tiger Truck Stop in Grosse Tete, Louisiana since 2000. She has also worked with Physicians Committee for Responsible Medicine to promote cosmetics that are not tested on animals.
