Peace lilies droop dramatically, which makes them useful and slightly theatrical. The leaves can collapse when the plant is thirsty, but wet soil can cause drooping too.
Quick Answer
A peace lily droops because of underwatering, overwatering, heat, low humidity, or root stress. Check the soil before watering.
Dry Soil
If soil is dry and the plant droops, water thoroughly. Peace lilies often perk up within hours.
Wet Soil
If soil is wet and the plant droops, roots may be stressed. Stop watering and check drainage. Repot if roots are rotten.
Light and Heat
Peace lilies prefer bright indirect light. Direct hot sun or heat vents can make leaves wilt.
Bottom Line
Peace lily droop is easy to misread. Dry soil means water. Wet soil means pause and inspect.