In China, he passed the civil-service examination. Around 725, he took an administrative position and was promoted in Luoyang in 728 and 731. Around 733 he received Tajihi Hironari, who would command the Japanese diplomatic mission. In 734 he tried to return to Japan but the ship to take him back sank not long into the journey, forcing him to remain in China for several more years. In 752, he tried again to return, with the mission to China led by Fujiwara no Kiyokawa, but the ship he was traveling in was wrecked and ran aground off the coast of Vietnam, but he managed to return to Chang'an in 755.
When the An Lushan Rebellion started later that year, it was unsafe to return to Japan and Nakamaro abandoned his hopes of returning to his homeland. He took several government offices and rose to the position of Governor-General of Annam between 761 and 767, residing in Hanoi. He then returned to Chang'an and was planning his return to Japan when he died in 770.