On February 16, 1968, the Belgian government placed an order for Mirage 5 aircraft to replace its outdated F-84F Thunderstreak and RF-84F Thunderflash fighter jets. The plan was to purchase 88 aircraft, including 54 Mirage 5BA with American electronics, 22 Mirage 5BR reconnaissance aircraft, and 12 two-seater Mirage 5BD trainers. Prior to this decision, the Belgian military had spent several years studying various aircraft, including the F-5, A-7A Corsair, A-4 Skyhawk, and A-6A Intruder. They also considered potential upgrades to other aircraft, such as the F-104H and Draken. Ultimately, however, the Mirage 5 was deemed the best option. The aircraft remained in service with the Belgian Air Force until the end of the Cold War. Afterward, 20 units were sold to Chile as the Elkan, and the remaining aircraft were donated to museums or sold to the French company SAGEM.

The Belgian Mirage 5BA was introduced in Update 2.37 "Seek & Destroy" as a part of the French aviation research tree. It is a maneuverable fighter with good missiles. However, it has a small amount of missiles and small cannon ammunition, and it lacks guided air-to-ground weapons. It differs from the French Mirage 5F in that it has countermeasures.