"If the Islamic Revolution had not occurred, liberalism and Marxism would have crushed all human dignity in their power-seeking and money-grubbing claws. Nothing would have remained of human and spiritual principles," he added.
Ahmadinejad said that in the three decades of its history, the Islamic Revolution had inspired some great developments in the world.
The Iranian president made the remarks as the 31st anniversary of the Islamic Revolution approaches.
Iranians are expected to pour into the streets on February 11 to celebrate the occasion in public rallies across the country, as they have done annually over the past three decades.