Haber, 55, is currently Germany's ambassador to Beirut and has been envoy to Moscow and Ankara. He will take charge of some 200 European monitors who are expected to be deployed in Georgia by October 1.
Once on the ground, the EU mission will enable Russian peacekeepers to withdraw within 10 days from buffer zones near the rebel Georgian regions of Abkhazia and South Ossetia, whose independence Moscow has recognized.
Haber "will have a crucial role in putting together and launching the mission as a key part of the EU's efforts to address the crisis in Georgia and enhance stability in the region," EU foreign policy chief Javier Solana said.
"His range of skills and experience in diplomacy and crisis management will be assets for the mission. He has my full trust and support and I look forward to working with him," Solana added in a statement.