The singer posted a homemade video filmed backstage during her Monster Ball tour in Washington.
Gaga was wearing a white lace crown emblazoned with the Twitter logo and holding a fluorescent blue wand.
She said: "Hello world, this is Lady Gaga, Queen of Twitter, I would like to thank all my beautiful little monsters for following me."
Gaga's message was accompanied by a xylophone, before a bird on a string suddenly floated into the shot only to be sent off by the star with a kiss.
