During disaster times, we need specific information to rapidly plan a disaster response, especially in sudden-onset disasters. Due to the inadequate capacity of Routine Health Information Systems (RHIS), many developing countries face a lack of quality pre-disaster health-related data and efficient post-disaster data processes in the immediate aftermath of a disaster. Considering the significance of local capacity during the early stages of disaster response, RHIS at local, provincial/state and national levels need to be strengthened so that they provide relief personnel up-to-date information to plan, organize and monitor immediate relief activities. RHIS professionals should be aware of specific information needs in disaster response (according to the Sphere Project’s Humanitarian Minimum Standards) and requirements in data processes to fulfil those information needs. Preparing RHIS for disasters can be guided by key RHIS-strengthening frameworks; and disaster preparedness must be incorporated into countries’ RHIS. Mechanisms must be established in non-disaster times and maintained between RHIS and information systems of non-health sectors for exchanging disaster-related information and sharing technologies and cost.