In his first such statement in direct support of Khamenei since the June 12 election, the former president said "the current situation needs everyone to observe the leader's decrees and advice," Iranian news agencies reported.
Rafsanjani was speaking at the start of a meeting of Iran's top political arbitration body, the Expediency Council, which he heads.
He urged the bitterly divided groups to create "appropriate conditions to act and commit to the constitution … and confront law breakers, whatever their ideological leanings."
A supporter of the opposition, Rafsanjani distanced himself from Khamenei in a Friday prayer sermon last month and said the election had triggered a "crisis" in the country.
His comments, which came after a month of street protests marred by violence, were seen as a defiant stance in contradiction to the one adopted by Khamenei, who publicly defended Ahmadinejad's victory.
On Saturday, Rafsanjani called for the current "excited and emotional atmosphere" to be replaced by a "wise one."
He said authorities must follow Khamenei's advice also on the issue of political detainees jailed in the aftermath of the election.
"The way out of the current situation is commitment to the leader's advice on detainees of recent events and retrieving the rights of those whose rights have been violated," he said.
Opposition leaders, mainly defeated presidential candidate Mehdi Karroubi, have charged that detainees have been raped, tortured and beaten in prisons.
The authorities have dismissed these allegations, but closed a detention centre south of Tehran following orders from Khamenei.
Rafsanjani also reiterated a previous call for the media to avoid fuelling "disunity" in society.
