The disclosure provides a read-write separation and automatic scaling-based cloud arrangement system and method. Thus, a read operation and a write operation are separated. Capacity expansion and capacity reduction are performed on a cluster. All index data is stored in corresponding object storage. A pre-computing module submits resources (memory and CPU) required by a computing task to an automatic scaling module. Resource creation is performed by invoking API corresponding to an infrastructure automated arrangement tool Terraform, to guarantee the operation of a construction task. The automatic scaling module provides two resource expansion strategies, which are based on time and the maximum number of waiting tasks. According to the disclosure, the utilization rate of cloud resources is increased, costs are lowered, and manual intervention is reduced. Therefore, higher reliability is provided for the horizontal expansion of a query cluster, the stability of a system during high concurrency is enhanced, and the safety and infinite scalability of data are guaranteed.