Syria's defence ministry said on Sunday it had taken over the Al-Shadadi base in the northeast from US forces, days after assuming control of a facility near the Jordan-Iraq borders.
"The forces of the Syrian Arab Army have taken over the Al-Shadadi military base in the Hasakeh countryside following coordination with the American side," a ministry statement said.
US forces operating as part of the international coalition against the Islamic State group had been stationed at the base outside the town of the same name.
The town housed a prison where Kurdish forces detained members of the extremist jihadist organisation, before government forces advanced into the area last month.
Sunday's announcement follows US confirmation on Thursday that its forces had vacated Al-Tanf base near Syria's borders with Jordan and Iraq.
The Kurdish-led Syrian Democratic Forces (SDF) were a major partner of the US-led international coalition against IS, and were instrumental in the group's territorial defeat in Syria in 2019.
But following the fall in December 2024 of longtime ruler Bashar al-Assad, the United States has drawn closer to the new government in Damascus, recently declaring that the need for its alliance with the Kurds had largely passed.
Despite IS's territorial defeat, the group remains active, however.
On Saturday, the US Central Command said its forces had struck more than 30 IS targets in Syria this month.
A CENTCOM statement said the air strikes between February 3 and 12 hit IS "infrastructure and weapons storage targets".