Newman, who lives with his wife in a retirement community in Palo Alto, Calif., said little about his time in captivity as he was reunited with his family at San Francisco International, the San Jose Mercury News reported.
He arrived on a United Airlines flight from Beijing.
It's been a great homecoming," he said, smiling, adding that his first action when he got home would probably be to "take my shoes off."
Newman said he was grateful for the support he received during his detention.
North Korea's state news agency, KCNA, reported Newman had been "deported."
"I'm very glad to be on my way home," Newman told reporters after arriving in Beijing. "And I appreciate the tolerance the DPRK [North Korean] government has given to me to be on my way."
Newman had read from an alleged confession last week in which he admitted working with South Korean forces during the Korean War in the 1950s.
The KCNA report said North Korea had acted from a "humanitarian viewpoint" in releasing Newman, "taking into consideration his admittance of the act committed by him on the basis of his wrong understanding [and the] apology made by him for it, his sincere repentance of it and his advanced age and health condition."
Newman was visiting North Korea on a 10-day tour in October when he was pulled off a plane in Pyongyang as he was about to depart. After acknowledging his detention weeks later, the North Korean government said he engaged in war crimes as a young Army officer and had come to the country as a spy.
Newman was involved during the Korean War with training Koreans to work behind enemy lines, the Mercury News reported. The newspaper said before traveling to North Korea he had been in touch with some of his surviving comrades in South Korea and had asked them if they had messages for relatives in the north in an email released by North Korea.
He had planned to visit South Korea, and veterans waited for him at the Seoul airport on Oct. 27 with flowers.
Vice President Joe Biden, during a visit to Seoul, applauded Newman's release.
He said he spoke to Newman after a wreath-laying ceremony at the War Memorial of Korea.
"I offered him a ride home on Air Force Two, but as he pointed out, there's a direct flight to San Francisco, so I don't blame him, I'd be on that flight too," the vice president said in a pool report.
Biden urged North Korea to release Kenneth Bae, an American missionary and tour operator held since November 2012.