Hu Shigen,has also been deprived of his political rights for five years, the No 2 Intermediate People's Court in Tianjin which conducted the trial said in its verdict.
Hu, 61, pleaded guilty and said he will not appeal.
He had been in prison previously, serving 14 years of a 20 year sentence from 1994 to 2008 for inciting, organising and leading "counter-revolutionary" activities.
His brief trial came a day after the court issued a suspended three-year sentence to activist Zhai Yanmin. Both were arrested in July last year with two others as part of a nationwide crackdown on legal rights activists. About 300 lawyers and activists were initially seized and questioned before most were released.
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Since 2009, he has used illegal religious organisation to attract illicit lawyers and paid petitioners to spread subversive thoughts and ideas, state-run Xinhua news agency said in its report.
In addition, he arranged for Gou Hongguo, another suspect, to receive anti-China training overseas, the court said in a statement.
He conspired and plotted to subvert state power with others, including Zhou Shifeng, Li Heping and Zhai and established "a systematic ideology, method and steps" to achieve it.
"I recognise the severity of my crimes, and the huge damage I've brought to the country, society, my family and myself," the report quoted Hu as saying in his final statement.
He thanked the government for looking after him while he was ill and in hospital.
"I want to thank the police, procuratorate, judges and medical staff for their help and education, which has been more memorable than any time before. I am resolved not to participate in any activities against the Party and government in the future, and be a citizen abiding by the law," hesaid.