The Hispano-Suiza 12X was an aircraft piston engine designed in France by Hispano-Suiza during the early 1930s. A 12-cylinder Vee, liquid-cooled design, the 12X was used on several aircraft types, some of them being used in limited numbers during World War II. Due to the 12X's limited power output, its derivative the more powerful Hispano-Suiza 12Y had a longer career.

Hispano-Suiza is a Spanish automotive company. It was founded in 1904 by Marc Birkigt and Damián Mateu as an automobile manufacturer and eventually had several factories in Spain and France that produced luxury cars, aircraft engines, trucks and weapons.