Portman has been a vegetarian since childhood and is an advocate for animal rights. She does not eat animal products or wear fur, feathers or leather. "All of my shoes are from Target and Stella McCartney", she says. It has been reported that she will appear alongside actress Elissa Sursara in a PETA PSA to support the groups anti-fur campaign at some point throughout 2009. In 2007, Natalie Portman traveled to Rwanda with Jack Hanna, to film a documentary titled Gorillas on the Brink. Later at a naming ceremony, Portman named a baby gorilla Gukina, which means 'to play'. In 2007, she launched her own brand of vegan footwear. Portman has been an advocate of environmental causes since childhood, when she joined an environmental song and dance troupe known as World Patrol Kids.

Portman has been involved with the 2004 presidential campaign of Democratic candidate John Kerry and with antipoverty activities. In 2004 and 2005 she traveled to Uganda, Guatemala, and Ecuador as the Amba