Robinson, now serving as a U.N. special envoy for the Great Lakes region of Africa, visited the DRC's eastern North Kivu province to examine progress since rebel conflict last year.
The rebel March 23 Movement seized control over parts of eastern DRC in late 2012. Former M23 leader Bosco Ntaganda surrendered to the International Criminal Court, where he's the subject of arrest warrants for war crimes committed in DRC.
Robinson said she was encouraged by a measure signed by 11 countries in the region in February that was meant to address ongoing issues in DRC.
"This is a moment when things must come together," she said in a statement. "We need peace, security and economic development in eastern DRC and the region going forward."
The U.N. mission in DRC said about 1,500 civilians sought refuge near a peacekeeping base in eastern DRC in early April. They fled the area near the Rwandan border following clashes between Congolese and rebel forces.
The U.S. State Department said in April that it was concerned about the security situation in the DRC.