The new note for 50,000 rials worth about $6.30 also reflected rising inflation, a fact that has brought criticism of President Mahmoud Ahmadinejad's policies. It is worth more than twice the previously highest denomination note.
The note is printed in orange, green and blue and shows a nuclear symbol within a map of Iran. A brief text next to the symbol gives a quote from the Prophet Muhammad: "Men from the land of Persia will attain scientific knowledge even if it is as far as the Pleiades." Pleiades is a cluster of stars.
In conformity with the law, the note also bears a portrait of the late Ayatollah Ruhollah Khomeini, the father of the 1979 Islamic Revolution.
State television said the Central Bank had issued six million of the new notes, and will introduce another six million within two weeks.
The nuclear program is a source of national pride in Iran. Even government opponents support the program. In recent months, however, reformists and conservatives have criticized Ahmadinejad's harsh rhetoric, saying it has brought more harm than good.
Iran has rejected UN demands that it halt enrichment, insisting its nuclear program is peaceful and aimed at producing energy. The U.S. and its European allies are concerned its real aim is to produce nuclear weapons.
Enriched uranium is used as fuel in nuclear reactors, but if enriched to a higher level, it can be used in atomic bombs.
The UN Security Council imposed sanctions on Iran in December after it ignored a resolution demanding that it halt enrichment. The five permanent members of the council plus Germany are now considering further sanctions against Iran.