Nessa is the last-mentioned, and perhaps least, of the Vala in J.R.R. Tolkien's mythology. Her portfolio is obscure, seemingly limited to Dance, although she has an affinity to deer. She is the sister to Oromë.

Nessa is little mentioned in the Quenta Silmarillion. Her sole appearance is as follows. On her wedding day to Tulkas, she danced before all of Valinor. That night, she tired Tulkas out. Melkor knew that his greatest foe would be deep asleep, and chose that time to escape.