The 38-year-old's first tweet comes complete with a video clip in which she explains that she is trying to join the 21st century.
Paltrow said: 'So it's me, I'm on Facebook and Twitter, but not right now. I'm walking down the street looking for a cab.'
In a matter of hours, Gwyneth had 66,000 followers on Twitter and had been liked more than 48,000 times by Facebook fans.
The Country Strong actress already has a newsletter, website, Facebook page and Twitter account for GOOP, her lifestyle venture.