An Ebola outbreak started in December 2013 in Guinea and spread to Liberia and Sierra Leone in 2014. The health systems in place in the three countries lacked the infrastructure and the preparation to respond to the outbreak promptly and the World Health Organisation (WHO) declared a public health emergency of international concern on August 8 2014. The aim of this study was to determine the effects of health systems' organisation and performance on the West African Ebola outbreak in Guinea, Liberia and Sierra Leone and lessons learned. The WHO health system building blocks were used to evaluate the performance of the health systems in these countries. A systematic review was conducted supplemented by expert interviews to gain experts inputs on how Ebola and health systems were linked. Lack of health workforce was found to have the biggest detrimental effect and it was the most affected building block during the outbreak. Adequate service delivery results from collective success of the other blocks. Health financing and its management is crucial to ensure availability of medical products, fund payments to staff and purchase necessary equipment.