The invention relates to a nuclear grade cooling tower, comprising a tower body. The tower body comprises at least one air outlet and at least one air inlet, and the inner of the tower body is provided with a fan, a water collector, a water distributor and fillers from top to bottom. The fan is used to generate the circulating air which can exchange heat with water in the water collector, in the water distributor and in the fillers to decrease the temperature in the tower. The tower is characterized in that a baffle of the air outlet is arranged in the tower body between the fan and the air outlet, and the baffle is used to avoid the influence on normal operation of the fan by the objects or strong airflow passing the air outlet. Due to the baffle of the air outlet arranged in the tower body between the fan and the air outlet, the nuclear grade cooling tower has high safety precautions, thereby ensuring the normal operation under the conditions of falling objects and strong airflow impact caused by explosion, and the severe natural conditions such as the tornado and the like.