Huang Jinqiu was detained by the Chinese government on September 13 last year and is being held in Changzhou, Jiangsu province, the Free China Movement said.
His family members were only recently notified.
"My son came back to China from Malaysia where he had been studying. Before he went overseas he was a journalist with Guangzhou Evening News," his father Huang Guide told AFP.
"I don't know what he is supposed to have done but I know he is innocent. He has no power and no money. What was he supposed to have done?"
Huang said he was being prevented from seeing his son and had heard nothing about a trial date.
The Free China Movement, which gave no details about what Huang's subversion charges relate to, called for his immediate release.