Abstract: To solve the problem of difficulty in matching the planned capacity and actual usage requirements of the voice call system of the China Railway Group Companies, this paper designed a highly elastic intelligent voice call system by collaborating with the voice call systems of multiple China Railway Group Companies. The paper adopted cloud computing technology to implement high scalability, prioritized user queues based on the sensitivity level of calling users to enhance business inclusiveness. The system has been applied in the emergency command platform of China Railway Guangzhou Group Co. Ltd. and has achieved good results.