"I believe, if I were in his shoes, I would step down," the king said. "I would step down and make sure whoever comes behind me has the ability to change the status quo that we're seeing."
Jordan has been critical of Syria's crackdown on anti-government protesters in recent months.
King Abdullah said Assad should usher in a new era of political dialogue before stepping down.
"Again I don't think the system allows for that, so if Bashar has the interest of his country, he would step down, but he would also create an ability to reach out and start a new phase of Syrian political life."