Survivors of cluster bombs spoke at the conference
More than 100 nations, including the UK, have signed a treaty to ban current designs of cluster bombs.
Diplomats have agreed to back an international ban on the manufacture, use or stockpiling of the munitions, following 12 days of talks in Dublin.
Some 111 countries including the US, Russia and China have been urged to reconsider boycotting the treaty.
UK Prime Minister Gordon Brown has called the treaty a "big step forward to make the world a safer place".
UN Secretary General Ban Ki-Moon welcomed the landmark charter and encouraged all nations to sign up.
In his closing address to the conference, Irish Foreign Affairs Minister Micheal Martin said: "Rarely have we seen such single-minded determination to conclude a convention with such high humanitarian goals in such a concentrated period of time."
Mr Martin said he ultimately wanted to see the treaty ratified by all member states of the United Nations.
"We must work together to explain and argue for its provisions with those who are not here," he said.
Mr Ban said: "I place the full facilities of the UN at the disposal of member nations to help them secure a speedy ratification."
The draft treaty will be signed by world leaders in Oslo on 3 December and then individually ratified by each nation.
Cluster bombs have been used in countries including Cambodia, Kosovo, Afghanistan and Lebanon.
They are made up of a big container that opens in mid-air, dropping hundreds of smaller individual sub-munitions, or "bomblets", across a wide area.
Countries like the US, India, Pakistan and Israel claim such munitions are highly useful on the battlefield, but opponents say that where the bomblets fail to explode they leave a deadly legacy for civilians.
When details of the treaty were announced on Wednesday, the US said it would not alter its policy.
A statement from the Pentagon said: "While the United States shares the humanitarian concerns of those in Dublin, cluster munitions have demonstrated military utility, and their elimination from US stockpiles would put the lives of our soldiers and those of our coalition partners at risk."
The stockpile of cluster munitions the US military keeps at bases in the UK is one issue which has to be addressed.
The British representative at the talks in Dublin, John Duncan, said the UK would work with Washington to find a solution to the issue.
During the conference, delegates heard from survivors of cluster bomb attacks.
International Committee of the Red Cross official Peter Henby said: "It is sad that it took so long to get here and much more time and energy to implement it. But we have taken a momentous step forward."
Cluster Munitions Coalition spokesman Steve Goose said even nations who had not signed up would now be under pressure not to use the weapons.
He said: "We're certain that nations thinking of using the munitions won't want to face the international condemnation that will rain down upon them because the weapons have been stigmatised now."
HOW A CLUSTER BOMB WORKS
1. The cluster bomb, in this case a CBU-87, is dropped from a plane and can fly about nine miles before releasing its load of about 200 bomblets.
2. The canister starts to spin and opens at an altitude between 1,000m and 100m, spraying the bomblets across a wide area.
3. Each bomblet is the size of a soft drink can and contains hundreds of metal pieces. When it explodes, it can cause deadly injuries up to 25m away.