The country agreed to free 31-year-old Aijalon Mahli Gomes if Carter came to retrieve him.
The Boston resident was teaching English in South Korea, but was sent to eight years in a hard labor camp and fined $700,000 on Jan. 25 for allegedly crossing into North Korea and for an unspecified "hostile act."
Two officials who spoke anonymously because the sensitivity of the situation, told the Associated Press that Carter will spend one night in North Korea and will return with Gomes on Friday.
A senior U.S. official said that Carter is not representing the U.S. government and was going on the mission solely for humanitarian purposes. In early August, state department officials secretly took part in a failed mission to North Korea in attempt to free Gomes.
The case mirrors that of Laura Ling and Euna Lee, two American journalists detained in North Korea after they crossed illegally into North Korea. Former president Bill Clinton went to the country in August 2009 to secure their release at the request of the communist country.
It is not clear why Gomes entered North Korea. He had previously attended protests in Seoul in support of Robert Park, a U.S. missionary who entered the country to protest human rights abuses. Park was eventually released.Gomes had tried to commit suicide in the labor camp last month, North Korean news agencies reported.