The Ratana Sutta (Burmese: ရတနာသုတ်) (Sinhala: රතන සූත්‍රය) is a Buddhist discourse (Pali: sutta) found in the Pali Canon's Sutta Nipata (Snp 2.1) and Khuddakapatha (Khp 7); with a parallel in the Mahavastu. In the Pali it is seventeen verses in length, and in the Sanskrit version nineteen. The Ratana Sutta extols the characteristics of the three ratana (Pali for "gem" or "jewel" or "treasure") in Buddhism: the Enlightened One (Buddha), the Teaching (Dhamma) and the noble community of disciples (ariya Sangha).

In Theravada Buddhism, according to post-canonical Pali commentaries, the background story for the Ratana Sutta is that the town of Vesali (or Visala) was being plagued by disease, non-human beings and famine; in despair, the townspeople called upon the Buddha for aid; he had the Ven. Ananda go through town reciting this discourse leading to the dispersal of the town's woes.

The Ratana Sutta upholds the Three Jewels as follows:

In Theravadin Buddhist countries and also in Navayana, this discourse is often recited as part of religious, public and private ceremonies for the purpose of blessing new endeavors and dispelling inauspicious forces.