Mechanical energy input to the oceans is one of the most important factors controlling the oceanic general circulation. The atmosphere trans- ports mechanical energy to the oceans primarily through wind stress, plus changes of the sea level pressure (the so-called atmospheric loading). The rate of mechanical energy transfer into the ocean due to atmospheric loading is calculated, based on TOPEX/POSEIDON data over ten-year period (1993 -2002). The rate of total energy input for the world oceans is estimated at 0.04TW (1TW=1012Watt), and most of this energy input is concentrated in the Southern Oceans and the Storm Tracks in the Northern Hemisphere. This energy input varied greatly with time, and the amplitude of the interannual variability over the past ten years is about 15%.