The son of a German-Jewish garment-factory owner and an American mother, Newton attended the Heinrich-von-Treitschke-Realgymnasium and the American School in Berlin. Interested in photography from a young age, he worked for the German photographer Yva (Else Neulander Simon). Fleeing Nazi Germany in 1938 to escape persecution as a Jew, Newton worked briefly in Singapore as a photographer for the Straits Times before settling in Melbourne, Australia.

Newton settled in Paris in 1961 and began extensive work as a fashion photographer. His works appeared in magazines including, most significantly, French Vogue. He established a particular style marked by erotic, stylised scenes, often with sado-masochistic and fetishistic subtexts. A heart attack in 1970 slowed his output somewhat but he extended his work and his notoriety/fame greatly increased, notably with his 1980 "Big Nudes" series which marked the pinnacle of his erotic-urban style, underpinned with excellent technical skills. He also worked in portraiture and more fantastical studies.

Newton was extremely fond of his hometown of Berlin, and in October 2003 he donated an extensive photo collection to the Preußischer Kulturbesitz foundation (Foundation of Prussian Cultural Heritage). It is currently on display at the Museum of Photography near the Berlin-Zoo railway station.

In his later life, Newton lived in Monte Carlo and Los Angeles. He was killed when his car hit a wall in the driveway of the famous Chateau Marmont, the hotel on Sunset Boulevard which had for several years served as his residence in Southern California. It has been speculated that Newton suffered a heart attack in the moments before the collision. His ashes are buried in the Städtischen Friedhof III, Berlin-Schöneberg, Stubenrauchstraße 43-45. Schöneberg in Berlin, Germany.