Human Rights in China said Gao's younger brother and his father-in-law visited him Jan. 12.
Foreign human rights advocates had feared for Gao's life, The New York Times reported, as there hadn't been any word on his well-being since the family's last visit in March.
Human Rights in China said the brothers were told not to discuss prison conditions or the case against Gao, and were also not allowed to mention Gao's wife or children, who fled to the United States in 2009.
The Times said Gao is a human rights lawyer and Christian, and was detained after he took on touchy political cases, including defending ordinary citizens whose land had been unfairly seized.
The Times said Gao was sent to a prison in Xinjiang in 2011 for revoking his terms of suspension, and authorities said they would detain him for three years.
Gao said he suffered excruciating torture when he was previously detained in 2007.