After her retirement from the film industry, Brigitte Bardot launched Foundation Brigitte Bardot in 1986. The organization champions animal rights, fights against animal abuse, and rescues animals in France and other countries. The Herald reported that Bardot funded Foundation Brigitte Bardot by auctioning her possessions. Bardot's animal activism has led her to criticize various entities for animal cruelty, including France's President Emmanuel Macron and the Russian government. In addition, Bardot has condemned Canada since the late 1970s for its seal hunting.

In 2019, Bardot co-authored "Tears of Battle: An Animal Rights Memoir" about her journey into animal activism. In the book, Bardot disclosed why she decided she did not want to continue acting and why she chose animal activism instead. Per The Guardian, she wrote that the notoriety of being a star became too much, noting, "I know what it feels like to be hunted."

Bardot said of her acting career, "In the beginning, I enjoyed having people talking about me, but very quickly, it suffocated and destroyed me. Throughout my 20 years starring in movies, each time filming began, I would break out with herpes." She also said, "Humans have hurt me. Deeply. And it is only with animals, with nature, that I found peace."  While Bardot's dedication to animals is evident, she has used animal activism as a justification for spreading hate speech.