The death Wednesday of Modupeh Cole was announced by the health ministry, according to media reports in Freetown, the capital of Sierra Leone.
Trained in the US, Cole was one of the physicians in charge of the Connaught Hospital located in Freetown where Ebola patients are being treated.
Cole's death is a heavy blow to efforts to contain the Ebola epidemic in the country, which has a serious lack of professional healthcare personnel and infrastructure and has already been adversely affected by the death in July of Sheik Humarr Khan, who headed the programme against the disease.
Since the Ebola virus disease outbreak in March in Guinea Conakry and its spread later to Liberia, Sierra Leone and Nigeria, more than 1,000 people have died from the disease, according to World Health Organisation figures.
Despite the fact that African governments have mobilised all their resources with an eye toward containing the epidemic, the number of fatalities continues rising in West Africa, especially in Liberia, where 29 more people died Aug 7-9.
Ebola virus disease, which is transmitted by direct contact with the blood and body fluids of infected people or animals, causes serious haemorrhaging and can have a mortality rate of up to 90 percent.
This is the first time that an Ebola epidemic has been identified and confirmed in West Africa, with all previous outbreaks having been restricted to Central Africa.