A heat dissipation apparatus. A fan frame includes an air inlet, an air outlet, a passage, and a curved expansion portion. The air inlet is opposite the air outlet. The passage is between the air inlet and the air outlet, guiding airflow from the air inlet to the air outlet. The curved expansion portion is radially and outwardly extended from an inner peripheral wall of the passage at the air inlet or air outlet. An impeller is disposed in the fan frame and includes a plurality of blades. Each blade is disposed in the passage and includes an extension end extending to the curved expansion portion.