Howie Dorough was born to a Puerto Rican mother, Paula Flores, and an Irish American father, Hoke Dorough, the youngest of 5. Dorough had a passion for the entertainment business since he was three years old, when he would jump on his grandparents’ bed, singing "Baby Face" while strumming his tiny guitar. At the age of six, Dorough participated in an Orlando production of The Wizard of Oz to get his start in entertainment business.

Dorough auditioned for the Backstreet Boys where he reached worldwide fame along with group mates AJ McLean, Brian Littrell Kevin Richardsonand Nick Carter After the group reached stardom, Dorough and the rest of the band became staples on the covers of such magazines as Tiger Beat and 16 Magazine. In 1998, Howie's sister, Caroline Dorough-Cochran, died of Lupus. After her passing, Howie established the Dorough Lupus Foundation. The foundation helps raise awareness about the disease, financial support for those who cannot afford treatment, and money for research. To date over half a million dollars have been raised for finding a cure.

As one of the four contributing voices to the Backstreet Boys Howie is notable for his high falsetto. Being the countertenor, he has usually sung the highest harmony in the choruses, and is notable for being a normal choice for ballads, where he has taken over some slow-tempoed lines ('I Want It That Way', 'Drowning', 'The Answer To Our Life', 'The Perfect Fan', 'Show Me The Meaning Of Being Lonely').

Howie has sung lead on several Backstreet Boystracks, the most notable being "Spanish Eyes" from the Millennium album and two tracks that he penned himself: "What Makes You Different (Makes You Beautiful)" and "How Did I Fall In Love With You" sung with Kenneth "Babyface" Edmonds(Black and Blue).

Still he's mostly the official two-part harmoniser of the group, often supporting either Brian, Nick or AJ, while they're singing solo. However, on the latest album "Unbreakable," Howie's voice has been more noticeable in many of the songs; this is because Kevin Richardsondidn't participate in this album. Moreover, Howie has mostly replaced Kevin's part in live concerts when they perform old songs, such as in an I Want It That Way performance in Japan, even though they have completely different vocal ranges.

On August 16, 2007, Dorough announced his engagement to long-time girlfriend Leigh Boniello. Dorough and Boniello, a film executive turned real estate broker, met in 2000 during the Backstreet Boys Into the Millennium tour, where Boniello was serving as webmaster to the group's official site. Dorough proposed to Boniello on New Year's Eve and married on December 8, 2007.