Initial phase of the new facility is scheduled to be opened within eight weeks, and it will be built and managed by British military engineers and medical staff.
The new facility, to be built near Freetown the capital of Sierra Leone, will treat Ebola victims, including local and international health workers and volunteers.
The UK’s commitment to build the treatment facility follows a direct request from the World Health Organisation (WHO) and the government of Sierra Leone for assistance in containing the Ebola outbreak.
Currently, the UK Government is working with Save the Children to design a long term plan to manage and operate the facility once it is fully set up.
UK International Development Secretary Justine Greening said Britain is at the forefront of the global effort to tackle this deadly outbreak, having already committed £25m of support, including frontline treatment and funding for medical research to develop a vaccine.
"The scale of the problem requires the entire international community to do more to assist the affected countries which is why the UK is working with the government of Sierra Leone to build a new medical treatment facility near their capital Freetown," Greening said.
"When it is up and running it will enable the UK to provide medical care for local and international health workers, as well as treatment for the wider population."
Following completion, the new medical facility will include a 50 bed medical unit for treating victims of the disease as well as a specialist 12 bed treatment centre for health workers, including any local or international medical volunteers.
Save the Children chief executive Justin Forsyth said ebola threatens thousands of people’s lives across West Africa and could set back development many decades.
"The key to combatting this epidemic is backing front line health workers and underpinning a fractured health system in Sierra Leone – without urgent action to assist medics, many more children and their families will suffer and die from this most appalling and tragic disease," Forsyth said.
"Save the Children is working alongside DFID and the MoD on a feasibility study to cement plans to firstly help set up the centre and then take it over with international experts, as well as local staff, to provide the very best life-saving health service under the most challenging conditions."