The invention provides a low-temperature negative-pressure cross-flow type cooling tower which comprises a tower body and a ventilation cylinder. The ventilation cylinder is fixed above the tower body, and a draught fan is arranged in the ventilation cylinder; the tower body comprises an inlet-air plate, a heat-dissipation system and a spray-water system, wherein multiple air inlets are formed in the inlet-air plate, and a wind block is arranged on the inner wall of each air inlet, the wind block can cover the air inlet. When the draught fan rotates, the wind blocks are opened by cold air, and then the cold air enters into the heat-dissipation system from the air inlets. As the draught fan rotates, air in the tower body is discharged, so that negative pressure is produced in the tower body, the wind blocks are opened by environmental air, and the environmental air enters into the tower body from the air inlets for cooling. When the environment temperature is changed, the pressure of the environment atmosphere is also changed, and then the gas pressure difference between the interior of the tower body and the exterior of the tower body is changed, as the wind block itself has gravity, the opening angle of the wind block is also changed, thus regulation of air inflow is achieved, and cooling effect is improved.