The MB.81 was a French military aircraft built by Société des Avions Marcel Bloch as a flying ambulance since it was designed to carry one passenger, in or out of a stretcher.

Developed in response to a government-sponsored competition in support of the new doctrine of "aerial first aid", it was employed exclusively in the overseas colonies, specifically Morocco and Syria.

The main design feature made it possible to transport a casualty lying prone, in a compartment placed between the pilot and the engine.

The wings could also be adapted to hold casualties, remaining constantly under the sight of the pilot and connected to him by an Aviaphone communication system.

The aircraft was built without any assistance from the government, but an initial order of 20 was placed by the Ground French Forces (the French Armée de l'Air was founded in 1933), and it was one of the aircraft that relaunched Marcel Bloch in the aeronautical construction industry.