M23 rebels on Friday handed over the Rumangabo army base to east African regional forces, after nearly two months in charge.
At a brief ceremony held at the facility, a rebel representative said the gesture symbolizes the group's commitment to peace.
A summit held in the Angolan capital last November ordered the rebels to vacate all Congolese territory under their occupation.
The Rumangabo base located in the Rutshuru territory fell to the rebels in November.
In December, the rebels withdrew from another strategic town of Kibumba but have since gone on to capture more territory.
The Congolese military has called the withdrawals a sham.
The M23's resurgence has cratered relations between the DRC and its smaller central African neighbour Rwanda, which Kinshasa accuses of backing the rebels.
The United States, several European countries as well as United Nations experts agree that Rwanda is assisting the M23.
Kigali denies the charge, and accuses the Congolese government of colluding with the FDLR - a descendant of Rwandan Hutu extremist groups that carried out the 1994 Tutsi genocide in Rwanda.