The invention discloses an LED (Light-Emitting Diode) outdoor lamp with an external heat dissipation wind wheel and a method. The outdoor lamp consists of a wind turbine, a supporting air duct, a heat insulation shell, a light source, a light diffuser and a fresh air port. The method comprises the following steps that: the external heat dissipation wind wheel drives to exhaust airflow; and fresh air carries out heat dissipation on the light source through the fresh air port of the shell and flows through the supporting air duct and the wind turbine to be exhausted. The heat insulation shell is a hollow interlayer of which the outer layer is compounded with a heat insulating material, is applied to the LED outdoor lamp, has the capability of dissipating heat by utilizing the wind energy and has an obvious energy-saving effect. Due to adoption of the method disclosed by the invention, the industrial, universal, series and standard production of the outdoor lamps and the improvement on the conventional outdoor lamps can be implemented.