Bruguera, who won the French Open in 1993 and 1994, takes over from Italy's Riccardo Piatti, as had been reported by French sports daily L'Equipe earlier in the day.
The 42-year-old Spaniard, a former world number three who won 12 titles mostly on clay, will work alongside France's Sebastien Grosjean as Gasquet's coach.
Piatti split with Gasquet earlier this month citing "purely personal reasons".
"The three seasons that I spent with Richard Gasquet were very important for me," explained the former coach of Novak Djokovic and Ivan Ljubicic, adding he had "other projects" he wanted to pursue.
Former Grand Slam champ Sergi Bruguera to coach Richard Gasquet
Advertisement