The US-based activist group Human Rights Activists News Agency (HRANA) and the human rights organization Abdorrahman Boroumand Center said in separate statements that they were convicted of throwing concrete blocks from a residential building at security forces in the capital. It is unclear when the verdict was handed down.
One of the four is believed to be the first woman sentenced to death in connection with the protests.
Seven people have previously been hanged in connection with the protests that culminated in the first weeks of the year.
Human rights organizations accuse Iran of using the death penalty as a tool of repression to instill fear in the population.
