Huang Qi's mother says police went to Huang's home in the city of Chengdu this afternoon and produced a summons before taking him away.
Pu Wenqing, Huang's mother, says police searched their home and seized five computers, two mobile phones and other equipment.
Huang founded a rights monitoring website and has long been one of China's most outspoken advocates for the rights of people who try to bring their grievances to the attention of the government but often face police harassment.