Her album Born This Way sold 215,000 copies in its first week – more than the rest of the top 10 put together.
Adele’s second album, 21, has slipped to number two after spending 16 of the last 21 weeks in the top spot.
The British soul singer is also in third place with her debut album 19.
Lady Gaga’s debut The Fame is also still selling well, at number seven.
The American star said: “I feel so honoured to have the highest first week sales in the UK this year.
I wrote the album’s first single Born This Way in Manchester because I was so inspired by the confidence and bravery characteristic of my fans.”
On the singles chart, US rapper Pitbull held on to the top spot for a second week with his debut single Give Me Everything featuring Ne-Yo, Afrojack and Nayer, according to the Official Charts Company.
