According to BBC, Sandy Phan-Gillis was sentenced to three and a half years in prison on Tuesday, but will not serve the time.
She had already spent more than two years in detention before her trial.
Phan-Gillis, who has Chinese origins but was born in Vietnam, was arrested in March 2015 while travelling in China with a business delegation from Texas.
Her husband Jeff Gillis said China had accused his wife of visiting the country twice on spy missions in 1996, and working with the FBI to capture two Chinese spies in the US and make them into double agents.
Speaking last year, he called the allegations "beyond ridiculous", and said her passport showed she did not travel to China in 1996.
UN Working Group on Arbitrary Detention previously denounced China's handling of the case, saying it had not observed "international norms relating to the right to a fair trial, and to liberty and security".
Phan-Gillis was reportedly held in a secret location for six months, and later placed in solitary confinement.
Mr Gillis said his wife had left China on Friday from the southern city of Guangzhou, and arrived in Los Angeles the same day.