Gaga is the most popular celebrity on Twitter with 10 million followers
She said: "10 Million Monsters! I'm speechless, we did it! It's an illness how I love you. Leaving London smiling."
Lady Gaga is headlining this year's Radio 1 Big Weekend, which is taking place in Carlisle.
The star became the first person to pass nine million followers on Twitter in March and overtook Britney Spears last August.
Britney Spears was only on top for three months after claiming the number one spot from Hollywood actor Ashton Kutcher.
Lady Gaga also has 24 million likes, or fans, on Facebook but is behind Eminem and the Facebook and Texas Hold'em Poker pages.
Lady Gaga has become the first celebrity to get more than 10 million followers on social networking site Twitter.
The US singer thanked fans for supporting her.She said: "10 Million Monsters! I'm speechless, we did it! It's an illness how I love you. Leaving London smiling."
Lady Gaga is headlining this year's Radio 1 Big Weekend, which is taking place in Carlisle.
The star became the first person to pass nine million followers on Twitter in March and overtook Britney Spears last August.
Britney Spears was only on top for three months after claiming the number one spot from Hollywood actor Ashton Kutcher.
Lady Gaga also has 24 million likes, or fans, on Facebook but is behind Eminem and the Facebook and Texas Hold'em Poker pages.