Samimi, 74, was released on 26 January from prison where he had been held since December 2020 on charges of "plotting against national security".
"Mr. Samimi was arrested on Thursday and we still have no further information about the department responsible for his arrest or his whereabouts," his family said.
After his release, the journalist met with numerous activists and political figures, including the reformist former president Mohammad Khatami (1997-2005).
His family said in January that Samimi was accused of "association against the security of the country" in another court case, without elaborating.
The previous month, the journalist had published a message from his cell in support of the protest movement sparked by the death on 16 September of Mahsa Amini, a 22-year-old Iranian Kurd, who died after being arrested by the morality police for violating the Islamic Republic's strict dress code.
In February 2022, Mr. Samimi was allowed to leave prison and return home due to health problems. But in May, he was re-jailed on suspicion of carrying out activities against national security upon his provisional release.
Mr. Samimi, former editor of the now-banned intellectual magazine Iran-e Farda ("Iran tomorrow" in Persian), was imprisoned several times before and after the 1979 Islamic Revolution.
© 2023 AFP