This paper describes the current distribution of cases of Buruli ulcer (BU) by highlighting health districts that are endemic and suspected to be endemic, based on the studies, surveys, and activity reports published from 1950 to 2013. We define as endemic any health district with BU patients positive by PCR, whether or not positive on a Ziehl-Neelsen (ZN) test, culture or histologic sample. A district is defined as suspected to be endemic when it is a historical BU area, has BU clinical cases and/or patients with positive ZN, but negative PCR. Of the 515 health districts in the DRC, 17 were found to be endemic (3%) and 26 suspected to be endemic (5%). In most cases, former focal areas, described before 1974, remain currently active. New focal points were found along the Kwango River in the province of Bandundu. We also discovered the extension of former BU focal areas to neighboring health districts in the provinces of Bas-Congo, Bandundu, and Maniema. The need for diagnostic confirmation by PCR appears to be a requirement and a priority, not only in all former historical focal areas but also in the health districts newly suspected to be endemic.