Gaura Purnima is a Vaishnava festival celebrating the birth of Chaitanya Mahaprabhu (1486–1534), founder of Gaudiya Vaishnavism. It occurs on the purnima (full moon day) of the month of Phalguna, which usually falls in March or April.

Gaura Purnima means “Golden Full Moon”, a reference to Chaitanya. His followers spend this festival fasting and singing in congregation, then at moonrise everyone participates in a feast.

Chaitanya Mahaprabhu, born Vishvambhar Mishra, was a 15th-century Indian saint from Bengal, considered to be the combined avatar of Radha and Krishna by his disciples and various scriptures.
The way Chaitanya Mahaprabhu worshiped Krishna with bhajan-kirtans and dance had a profound effect on Vaishnavism in Bengal.

He was also the main proponent of the Vedantic philosophy of Achintya Bheda Abheda Tattva. Mahaprabhu founded Gaudiya Vaishnavism (also known as Brahma-Madhva-Gaudiya Sampradaya). He expounded Bhakti yoga and popularized the chanting of the Hare Krishna Maha-mantra.

He composed the Shikshashtakam (eight devotional prayers) of which a small collection of commentaries by Srila Bhaktivinoda Thakura, Srila Bhaktisiddhanta Sarasvati, A.C. has been printed. Bhaktivedanta Swami Prabhupada (you can find her at Villa Vrindavana)

Chaitanya is sometimes called Gauranga or Gaura due to his complexion resembling molten gold.

His birthday is celebrated as Gaura-purnima.