Hughes re-joins the club as a free agent having previously been at south-coast rivals Portsmouth.
The experienced 33-year-old, a former Scotland international, spent nine years at Pompey where he made 131 league appearances.
His signing marks a return to the club where he started his professional career in 1998 after coming through the youth system at Arsenal.
In his first spell at Bournemouth, he was part of the side that twice went close to reaching the play-offs.
Hughes made more than 130 league appearances for the Cherries before joining Portsmouth.