Mashallah Karami was sentenced to six years in prison by a Revolutionary Court in the Tehran satellite city of Karaj on charges of illegally organising gatherings and collecting donations, his lawyer Ali Sharifzadeh Ardakani said on X, adding that the verdict had "flaws" and would be appealed.
The accused's son Mohammad Mehdi Karami was executed in January 2023 over the killing of a paramilitary two months earlier at the height of protests sparked by the death in custody of Mahsa Amini, who had been arrested for an alleged breach of Iran's mandatory dress code for women.
Mashallah Karami had posted videos on social media pleading for his son's life to be spared.
When his pleas fell on deaf ears and his son was executed, he posted footage of the grave and of relatives and other supporters in mourning.
He was arrested in August 2023 and has remained in custody.
Human rights groups have urged the international community not to turn a blind eye to abuses by Iran following the death in a helicopter crash this month of president Ebrahim Raisi, himself a former prosecutor and judiciary chief.
Amnesty International said this week that at least eight people remained at risk of execution in Iran in cases related to the 2022 protests.
It said that authorities had "severely violated their fair trial rights and subjected many to torture and other ill-treatment, including beatings, electric shocks and sexual violence."
Amnesty said the nine people executed in protest-related cases so far, including Karami's son, had all been hanged after "grossly unfair sham trials".
Rights groups have repeatedly accused the authorities of harassing relatives of people killed in the crackdown on the 2022 protests and those hanged in the aftermath to prevent them from speaking out.
"The sentencing of Mashallah Karami, the father of an executed protester in Iran, to six years in prison is a stark illustration of the Islamic Republic of Iran's ruthless repression against families seeking justice," said the New York-based Center for Human Rights in Iran.
