The measures, reported by media at the weekend, are contained in a new family law that a top official said would be implemented by Iran's judiciary.
"A decree of divorce by mutual consent, without counselling, is forbidden," Parnian Ghavam, head of the judiciary's social work and counselling office, was quoted as saying by Tasnim news agency.
All Iranians filing for divorce would be obliged to go to a counsellor, she said. "From now on, without this it will not be possible to register divorces of mutual consent."
Iran's average divorce rate peaked at 21 percent last year, with big cities showing far higher rates.
One in three marriages fails in Tehran. In its northern quarter, home to the more affluent Western-leaning metropolitan elite, the figure is more than 40 percent. And most divorces are by mutual consent.
"The adviser's intention is to decrease the rate of divorce, in particular the rate of divorces of mutual consent," Ghavam was quoted as saying Saturday.
The official reasons for splitting up in Iran are a lack of affection, family interference, domestic violence and drug addiction.
Signup to our newsletter and follow us on Facebook and Twitter!
The new law says the aim of counselling is "to consolidate the foundations of the family and prevent an increase in family conflicts and divorce and try to create peace and reconciliation."
After counselling a couple, the state-appointed adviser's role is to assess if either partner has behavioural or character disorders.
If so the counsellor can rule that the couple needs more sessions and it is his or her word that a judge must act on in deciding whether or not to approve a divorce.
The judiciary reportedly has until February next year to fully establish the marriage counselling service but it was now in force.
Reformist newspaper Shargh reported Sunday that there were more than 30,000 divorces in Tehran alone last year, 90 percent of which were by mutual consent.
The enactment of the compulsory counselling measures coincides with broader concern in Iran about family breakdown and rising ages of those who get married.
Last month the government launched a matchmaking website in which clerics and professionals of good standing in their communities, such as doctors and teachers, will try to pair off young men and women.
Supreme leader Ayatollah Ali Khamenei, who wants Iran's population of 80 million to nearly double to 150 million by 2050, last year also urged officials to take new steps to improve the birth rate.
The government has since reversed past policies to control population growth, with legislation to cancel subsidies for condoms and birth control pills and eliminate free vasectomies.