The present disclosure relates to a method for automatically scaling a multi-container-based computational session on a cluster. The method includes: receiving, by a node controller, event information and statistical information about a container from a container engine; forwarding, by the node controller, the sensed event information and statistical information to a cluster controller; determining, by the cluster controller, whether to add or delete the container for a specific session based on the received event information and statistical information; forwarding, by the cluster controller, a container addition or deletion command to the node controller of the specific session according to a determination result; and determining, by the cluster controller, whether to add or delete the node by determining whether it is impossible to add the container only with an existing node or when it is necessary to delete the container.