President Chavez and his Iranian counterpart, Mahmoud Ahmadinejad, denounced the "imperialist" U.S. and advocated a "new world order."
"We are united and determined to end the current unjust order that dominates the world to substitute a new order based on justice," said President Ahmadinejad.
The MoUs provide notably the creation of a joint oil company, the participation of the Venezuelan oil company in the development of South Pars gas field and building a refinery in Syria, Iran's main Arab ally in the region.
Chavez arrived on Monday night for the ninth time to visit the Islamic Republic as part of an international tour aimed at strengthening trade links between Venezuela and several countries in Eastern Europe and the Near and Middle East.
Iran and Venezuela, Washington's black sheep, are bound by numerous cooperation agreements, about 80 in total, the Venezuelan ambassador to Tehran, especially in the energy, banking and industrial.
"In these 11 years, since online casino canada joining the Bolivarian revolution, our two countries, our two revolutions, have been built from scratch a world of new experiences, visions, horizons, roads," said Chavez.
Chavez, leader of the radical left in Latin America, does not miss any opportunity to recall the links between his country and Iran. Venezuela came close to Iran in recent years and is one of the few countries that defend the controversial Iranian nuclear program.
"At the time of new aggression against Iran that we will not stop the Islamic revolution, we again make clear our position on the unconditional support for Iran's sovereignty," he said Chávez in Tehran.
Iran is subject to over the summer to new international economic sanctions aimed mainly to banking and energy sectors, which are pulling out all the big Western companies.
Iran and Venezuela are also two influential members of OPEC, the Organization of Petroleum Exporting Countries, Tehran will be chairing the next January 1 for the first time since the 1979 Islamic revolution.
Ahmadinejad visited Venezuela in November 2009.