MEPs voted for the resolution by 339 to 202 after an emergency debate in Strasbourg.
The motion is not binding but it will add pressure on states to support a moratorium on the use of DU munitions.
During the debate Europe's foreign policy chief, Javier Solana, said he had seen no evidence of a link between the use of DU and cancer.
But he said nothing would be hidden in EU investigations into DU and any link that was discovered would be communicated immediately.
"We are all democracies. We have nothing to conceal," he said.
DU investigations
Nato special committee
European Commission working group
Individual Nato countries' inquiries
Several Nato member countries have expressed concern that incidences of cancer and other illnesses among soldiers who served as peacekeepers in the Balkans might have been caused by exposure to DU, which is mainly used in armour-piercing shells.
Seven Italians, five Belgians, two Dutch nationals, two Spaniards, a Portuguese and a Czech national have died after serving in the Balkans.
Mounting pressure
Mr Solana, who was secretary-general of Nato during the Balkan conflicts, said that the high profile controversy over the use of DU risked obscuring what was achieved in Bosnia and Kosovo.
Nato denies DU causes health problems, but in the face of mounting public fears decided last week to set up a special committee to investigate the concerns raised in several European countries.
Some individual Nato countries have already launched their own investigations, while the European Commission has set up a working group of medical and scientific experts that is due to report next month.
The commander of British forces in the Gulf War, General Sir Peter de la Billiere, has also joined calls for a thorough investigation into the possible health effects of DU ammunition.
Last week, the German Government said it could not establish a link between possible DU contamination and a blood related illness suffered by six German soldiers.
But a study commissioned by the German Ministry of Defence warned that steps should be taken to prevent potential danger to the local population, particularly children, who may play in areas where DU weapons exploded, releasing toxic chemicals.
Earlier this week, it emerged that the United States military was concerned about weapons containing DU even before the Gulf War, exactly 10 years ago.