The present application relates to an energy storage system, which is adapted to be mounted on a base body, the energy storage system includes connecting assemblies, a cable and multiple battery modules, the cable is electrically connected with the connecting assemblies, the multiple battery modules are arranged on the base body through the connecting assemblies, and the multiple battery modules are electrically connected through the connecting assemblies. Multiple battery modules are provided according to the present application, the multiple battery modules are mounted on the base body through the connecting assemblies and are distributed in units.