From 2006 to 2013, the statistics shows that Taiwan ranked the lowest of total fertility rate among all the developed countries in the world. This phenomenon leads to more and more derelict school buildings as student population declines. Reactivating and reusing derelict school buildings has now become a primary task. On the other hand, while sub-replacement fertility caused the rise of ageing population ratio, designing a safe and healthy environment for the lives of the elderly is an essential issue for ageing society. The research focuses on the fire safety concerns of the long-term care center transformed from derelict school building. Under the AHP (Analytic Hierarchy Process) survey, a relative priorities of the selection criteria will be conducted to ensure the fire safety of the transformation from school building to long-term care center. The result from the survey shows that 'Fire Evacuation' is considered as the priority selection criteria of the transformation, whereas 'Accessible Environment Design' the last.