L
- Lawrance — U.S.
- Le Rhône — France
- LeBlond Aircraft Engine Corporation — U.S.
- Lee
- Lenape
- Les Long Long Harlequin
- Lessner
- LHTEC — U.S.
- Liberty
- Light
- Limbach Flugmotoren — Germany
- Limbach
- LMC - China
- Lincoln Motor — U.S.
- Lincoln
- Lockheed
- Lorraine-Dietrich — France
- Lotarev
- Lotarev — Russia/Soviet Union (see Ivchenko-Progress)
- Loughead Aircraft Mfg Co
- Lucas
- Lycoming
- Lyulka — Russia/Soviet Union
Read more about this topic: List Of Aircraft Engine Manufacturers