Aston reserve driver Vandoorne will share driving duties with team regular Lance Stroll, while Lando Norris and Oscar Piastri will have a day apiece for McLaren.
It will be the Belgian's first on-track outing in a current F1 car since he drove for Mercedes in the Abu Dhabi test in December 2020.
While the focus of the Spa test is on Pirelli's blanket-free tyres, it will give Vandoorne a valuable opportunity to sample the 2023 car, thus helping him with correlation of his simulator work for Aston Martin.
It will also make his life a lot easier should he be called upon if either Stroll or Fernando Alonso is indisposed at any point over the remainder of the season.
The 31-year-old shares the Aston reserve role with reigning Formula 2 champion Felipe Drugovich, with the pair taking turns to attend races on standby.
Drugovich had his own chance to sample the AMR23 when he drove it for two days at the Bahrain test in February while Stroll was not available. Since then, the Brazilian has been amassing further mileage in private testing in a 2021 car.
Under current rules, drivers doing in-season tyre testing must have at least one race start under their belt, hence Vandoorne's participation.
Along with his Aston duties, Vandoorne is also one of the drivers available to McLaren as a reserve, and his run at Spa would also make it easier for him to step into the MCL60 should he be required.
As well as giving him a general feel for 2023 downforce levels, the two cars share the Mercedes power unit and thus have similar settings on their respective steering wheels.
Vandoorne made his F1 race debut with McLaren in Bahrain in 2016, standing in for current Aston team-mate Alonso.
He then completed two full seasons in 2017 and 2018, the first with Honda power and the second with Renault. He finished 16th in the world championship in both seasons, with a best result of seventh place.
He was dropped by McLaren at the end of 2018 but he subsequently rebuilt his career in Formula E, winning the 2021-22 championship for Mercedes, for whom he also served as F1 reserve.
He currently drives for the DS Penske Formula E team, and is also a reserve for the Peugeot WEC outfit.
