The Belgian, who raced for the Marussia Virgin team in 2011 as well as having a one-off outing with Lotus at the 2012 Italian Grand Prix, has been seen in the Mercedes pits on several occasions this year alongside boss Toto Wolff.
Up until now, Mercedes explained that d'Ambrosio's presence was purely on an informal basis, as he was good friends with the squad.
However, the team was clear that he was not just having fun and there was the possibility of their relationship becoming something more serious.
Speaking at the Bahrain test last month, Wolff said: "He's been in Formula E and he's been a team principal of Venturi and finished second in the championship.
"And he's here as a friend, he's observing. Maybe something in the future, but not yet."
However, after being spotted in the paddock at the Saudi Arabian Grand Prix in Mercedes team kit, the outfit has confirmed that he has now taken a formal role with the squad.
In his new role, d'Ambrosio will help look after the host of young drivers that Mercedes has on its books in various categories around the world.
This will include duties at F1 races as well as managing the career and development of the racers who Mercedes hopes to bring up through the ranks.
These responsibilities had previously been the domain of James Vowles last year, before his departure to join Williams as its new team boss.
D'Ambrosio has most recently been focused in FE, having retired from racing at the end of the 2019/2020 season.
He moved up to a team management role with Venturi Racing the following campaign, eventually becoming team principal in November 2021.
Having helped the squad to its most successful season in 2021/2022, as it finished runner-up in the FE team's championship, he stepped down last September ahead of its transition to Maserati.
D'Ambrosio won three races in his time competing in FE, in Berlin in 2015, Mexico in 2016 and Marrakesh in 2019.
D’Ambrosio will work alongside Gwen Lagrue, who is responsible for the driver programme at Mercedes and has played a key role in the development of youngsters like Esteban Ocon and George Russell.
