The utility model belongs to an engineered safety system for a nuclear reactor, and in particular relates to a passive containment spraying-submerged cooling system. The passive containment spraying-submerged cooling system comprises a reinforced concrete shield building, wherein a containment is arranged in the reinforced concrete shield building, the containment and the reinforced concrete shield building are fixed together by a steel-concrete composite structure, a water-stop annular space is formed between the reinforced concrete shield building and the steel-concrete composite structure, and a passive containment spraying device is arranged above the containment. The passive containment spraying-submerged cooling system disclosed by the utility model has the advantage of realizing short-term and long-term cooling of the containment when the reactor is subjected to loss of coolant accident or main stream line rupture accident in combination with multiple extreme accidents, such as station blackout. The annular space between the containment and the shield building is of a water-stop structure and can be used for collecting residual spraying water.