Her death came less than two months after her latest release from a rehabilitation program and weeks following a disastrous performance where she was booed off a Belgrade stage by disappointed Serbian fans.
Winehouse died at the same age as four other music legends. Jimi Hendrix, Janis Joplin and Jim Morrison each died of drug overdoses when they were 27. Kurt Cobain was 27 when he committed suicide, soon after his release from rehab.
Police called the death "unexplained" early in their investigation.
London police said they were called to a home, which matches Winehouse's address, Saturday afternoon in response to "a woman found deceased."
"On arrival officers found the body of a 27-year-old female who was pronounced dead at the scene," a police statement said.
Winehouse canceled a European tour last month after being booed off stage
The "Rehab" singer had a history of battling drugs and alcohol and recently left a British rehab program that a representative said was intended to prepare her for scheduled European concerts.
The singer-songwriter left a rehab program in early June
She rose to fame in 2007 with her hit "Rehab"
But she cut short the European concert tour last month following a concert in Belgrade, Serbia, where she staggered around the stage and stumbled through several songs.
Audience members booed Winehouse off the stage that night just a few songs into the concert.
