Soltani, who together with Nobel Peace Prize winner Shirin Ebadi co-founded a rights center, has been sentenced to 13 years in prison by an appeal court.
Rights watchdog Amnesty says Soltani has been pressured to "confess" on camera that his rights center had received funding from foreign sources to encourage a "soft revolution" in Iran -- which the lawyer denies.
Amnesty continues to call on Iranian authorities to allow human rights defenders carry out their work without fear of persecution or harassment.
Soltani who has been in jail since 2010, was first sentenced to 18 years in prison in March.
Several of Soltani's colleagues have been also sentenced to jail.