New applications of information and communication technology (ICT) are shaping the way we understand and provide humanitarian medical assistance in situations of disaster, disease outbreak or conflict. Each new crisis appears to be accompanied by advancements in humanitarian technology, leading to significant improvements in the humanitarian aid sector. However, ICTs raise ethical questions that warrant attention. Focusing on the context of humanitarian medical assistance, we review key domains of ICT innovation. We then discuss ethical challenges and uncertainties associated with the development and application of new ICTs in humanitarian medical assistance, including avoiding harm, ensuring privacy and security, responding to inequalities, demonstrating respect, protecting relationships, and addressing expectations. In doing so, we emphasize the centrality of ethics in humanitarian ICT design, application and evaluation.