Abidal made over 200 appearances for Barcelona between 2007 and 2013 - winning four La Liga titles and two Champions Leagues during his time in Catalonia.
The 38-year-old has long been linked with a return to Barcelona in a staff capacity, and his new position with the club has now been confirmed.
"FC Barcelona announce that Robert Fernandez will not extend his contract as the football first team technical secretary which runs out on June 30 of this year," read a statement from Barcelona.
"The club would like to thank Robert Fernandez publicly for his commitment and dedication to FC Barcelona over the years and wishes him success in the future.
"Subsequently, FC Barcelona also announces that Eric Abidal will take over the role as football first team technical secretary. His presentation will be on Monday, July 18.
"The former Barca player returns to the club that he joined as a player in 2007 and where he won four league titles, two Copas del Rey, two Champions Leagues, four Spanish Super Cups, two Super Cups and two World Club Cups in his six seasons as a Blaugrana."
Barcelona won a La Liga and Copa del Rey double last term, but missed out on success in the Champions League.