Thousands have been forced to flee their homes because of the extremist group Islamic State (I.S.).
Cardinal Angelo Bagnasco said: "We cannot remain silent in the face of the project to cancel Christians from the Holy Land and other places."
I.S. has offered an ultimatum to Christians in many towns and villages it's taken over to convert to Islam, pay a tax or face death.
The Cardinal urged the West to take more action to stop what some have described as a genocide taking place in Iraq.
He added: "Our consciences must rebel against the cruel persecution killing Christians and other religious minorities in Iraq and other parts of the Earth."
The campaign of I.S. to wipe out Christianity was described as "an unacceptable disgrace".
He said if the West did not act it would be "unforgivable cowardice".