The property is located in Hampstead Heath, according to RealEstalker.com.
The gated, three-story bachelor pad includes four bedrooms and a high-tech security system to keep out fans and paparazzi.
The property also features a fully landscaped back garden and a multi-level terrace.
The boy band shot to fame after competing on Britain's "The X Factor." Styles recently told The Sun, "I like having fun but it's nice to just wake up in your own bed isn't it? I can see how you could get dragged into the bad stuff, but I've got good friends around me, good family. I think I've got my head screwed on."