The money will go to restocking Israel's Iron Dome defense, which has been credited with shooting down dozens of incoming rockets fired by Hamas during a three-week war.
An earlier version of the funding plan had failed on Thursday when Senate Republicans blocked a broader spending bill that was largely intended to provide money to handle the current immigration crisis at the US-Mexico border.
But lawmakers reached an agreement overnight to pass the missile funding measure.
To become law, the funding plan must still pass the House of Representatives and be signed by President Barack Obama. Given US lawmakers traditionally strong support for Israel, it is not expected to encounter significant resistance in the House.
Israel's Iron Dome missile interceptor system, which was partly funded by the United States, has shot down most of the rockets fired at its cities by militants in Gaza during the current three-week conflict.
Reuters and The Associated Press contributed to this report.