In 2000, Hudson married Chris Robinson, the frontman for The Black Crowes. They married on New Year's Eve in Aspen, Colorado. Hudson gave birth to their son, Ryder Russell Robinson, on January 7, 2004. The couple lived in a house that was once owned by director James Whale and traveled together during Hudson's film shoots or Robinson's music tours.[3] On August 14, 2006, Hudson's publicist announced that Hudson and Robinson had separated. Rumors swirled that the reason was Hudson's affair with Owen Wilson on the set of You, Me and Dupree.[12] On November 18, 2006, Robinson filed divorce papers, citing "irreconcilable differences".[13] The divorce was finalized on October 22, 2007.[14]

After she and Robinson separated, Hudson publicly dated Owen Wilson, her You, Me and Dupree co-star. However, the two broke up in May 2007. As of May 2008, she is said to be dating Lance Armstrong.

Hudson has noted that she is "not very religious,"[15] and describes herself as Jewish.[16] A vocal opponent of anti-Semitism in part because of witnessing it during a stay in Paris, Hudson has said, "I'm Jewish and this was the first time I experienced real anti-Semitism. Paris was scary...there were synagogues bombed and there was anti-Semitic graffiti all over the place. I was very angry. This is something I am passionate about".[17]

Hudson has also said that she does not enjoy seeing herself on screen, specifying that she "gets cold... shakes and... sweats" when watching her performances for the first time.[5] In July 2006, Hudson sued the British version of the National Enquirer after they had stated that she has an eating disorder and described her as "painfully thin." Hudson said that the tabloid's actions were "completely inappropriate" and a "blatant lie," and specified her concern relating the impressions about weight that she feels the tabloid could have on young girls