The present invention relates to an energy saving outlet, which comprises: a housing, having at least one first opening and a second opening thereon, for disposing the following elements at least one outlet, disposed in the housing and exposed the first opening, for providing an electrical equipment being plugged into; a sensor, disposed in the housing and exposed the second opening, for sensing a starting signal of the electrical equipment; a control unit, disposed in the housing and coupled to the sensor, for outputting a control signal when it receives the starting signal; a relay, one end being coupled to a power input terminal, and another end being coupled to the control unit, for being changed to an on or off state through the control signal; thereby the energy saving outlet can turn OFF its power when the electrical equipment has entered a stand-by state, so as to achieve the goal of energy saving. Furthermore, the present invention also provides an energy saving method by using an outlet.