Voters are set to give their verdict on President Rouhani's policy of opening up the country to the world.
The incumbent faces stiff competition from hardline cleric Ebrahim Raisi.
He's positioned himself as a defender of the poor - and called for a much tougher line with the West.
David Yeghnazar, the chief executive officer of Elam Ministries which ministers to the church in Iran told Premier's News Hour he's unconvinced either will be good news for believers.
He said: "Both the candidates are establishment figures, they're both committed to the Islamic revolution.
"In terms of whether it offers any hope of less persecution in Iran I wouldn't say Christians there are holding out for that.
"Under President Rouhani persecution has continued but there are fears if Raisi is elected the suffering could get worse."
Listen to David Yeghnazar speaking with Premier's Alex Williams: