Schwarzenegger dilahirkan dan dibesarkan di Los Angeles, California. Dia anak sulung dari Maria Shriver, wartawan dan pengarang yang merupakan seorang ahli keluarga Kennedy dan Arnold Schwarzenegger, seorang bina badan kelahiran Austria, pelakon, dan bekas Republikan Gabenor California.[2] Nenek sebelah ibunya, Eunice Kennedy Shriver, yang diasaskan Special Olympics dan adalah saudara perempuan Presiden John F. Kennedy, dan datuk sebelah ibunya, Sargent Shriver, adalah Duta Amerika Syarikat ke Perancis, pengarah pertama Peace Corps, dan naib presiden calon Demokrat dalam pilihan raya presiden Amerika Syarikat 1972.

Schwarzenegger has two older sisters, Katherine (born December 13, 1989) and Christina (born July 23, 1991),[1][3] a younger brother, Christopher (born September 27, 1997),[4] and a younger paternal half-brother, Joseph (born October 2, 1997).[5][6]

Schwarzenegger graduated from Brentwood High School in 2012.[7]Since 2012, he has been studying at the University of Southern California.[8]