Sadness (also called heavy-heartedness) is emotional pain associated with, or characterized by feelings of disadvantage, loss, despair, grief, helplessness, disappointment and sorrow. An individual experiencing sadness may become quiet or lethargic, and withdraw themselves from others. Crying is often an indication of sadness.

Sadness is one of the "six basic emotions" described by Paul Ekman, along with happiness, anger, surprise, fear and disgust.