Foreign ministers from the 27-nation bloc agreed to add the president, along with several leading officials, to an earlier blacklist.
"The repression in Syria continues," said British Foreign Secretary William Hague as he went into talks with his counterparts.
"It is important to see the right to peaceful protest, the release of political prisoners and taking the path of reform, not repression, in Syria over the coming days."
Tightening the screws on the Assad regime, the EU earlier this month issued an arms embargo as well as a visa ban and assets freeze against the president''s brother, four of his cousins, and others in his inner circle.
Assad could have avoided the sanctions by listening up to Syrian protestors and choosing the path of reform, said German Foreign Minister Guido Westerwelle.
"He did not choose this path. He continued to violently repress peaceful protests. This is why we must widen the sanctions, including against President Assad," he said.
"When a regime represses its own people this way, with violence, the EU must respond."
EU foreign policy chief Catherine Ashton had warned Assad earlier this month that he could be next on a new list of sanctions, but European nations had held off hitting out at the Syrian leader in hopes of seeing an end to the violence and a swift change to "genuine and comprehensive political reform".
Ashton said as she went into today's talks with EU foreign ministers that Syria's "government has to act now."