Belonging to the technical field of containment passive heat export, the invention in particular relates to a device for studying the influence of station blackout and in-containment large break accidents on a containment. An electric boiler is connected to a containment simulator respectively through a containment lower steam inlet pipeline and a containment upper steam inlet pipeline, a heat exchanger is placed in the containment simulator, two ends of the heat exchanger are connected to the bottom of a cooling water tank respectively through a natural circulation descending section pipelineand a natural circulation ascending section pipeline, the natural circulation descending section pipeline is equipped with a descending section isolation valve, the electric boiler is connected to asteam heating pipeline in the cooling water tank, and the pipeline is equipped with a water tank heating section isolation valve and a water tank heating section flowmeter. The device provided by theinvention is the experimental device used for a CNNCC Hualong No.1 containment passive heat export system for the first time at home to study the system response characteristic under the working condition that station blackout accident and large break extreme accident successively occur to a nuclear power station, and has great practical significance.