The former Iraqi Governing Council member escaped unhurt early on Wednesday after unidentified assailants opened fire on his convoy in southern Baghdad as he returned from Najaf, said spokesman Mithal al-Alusi.
"The doctor [Chalabi] is in good health. He is safe but two of his bodyguards were injured, " al-Alusi said.
Speaking to Aljazeera, the spokesman said the attack "was an attempt to prevent him from attending the Iraqi National Council which hopes to accelerate democracy in the country".
"The attackers are enemies of democracy who call for the return of the Baath party," he added.
Chalabi, a one-time Pentagon favourite who fell out of favour with the US, returned to Iraq from Iran earlier this month to face counterfeiting charges.
Meanwhile, several mortar rounds exploded at a checkpoint near the convention centre where delegates to Iraq's new National Council was meeting for the first time inside the heavily guarded Green Zone.
The US military said one person, an Iraqi, was wounded.
The council was expected to meet on Wednesday to organise oversight committees and draw up an agenda for the coming months.
The Green Zone houses the interim Iraqi government offices and the US embassy in a huge area along the banks of the Tigris River.