Photosynthesis may refer to:
- The enemy ability from Final Fantasy XI.
- The summon ability from Final Fantasy Legends: Toki no Suishō.
- The summon ability from Dissidia Final Fantasy.
- The summon ability from Dissidia 012 Final Fantasy.
- The Pop-up Duel Card from Final Fantasy Fables: Chocobo's Dungeon.
Photosynthesis is a process used by plants and other organisms to convert light energy, normally from the sun, into chemical energy that can be used to fuel the organisms' activities.