Kātyāyana or Mahākātyāyana (Sanskrit; Pali: Kaccāyana, sometimes shortened to Kaccāna; also Mahākaccāna, or Mahākaccāyana) was a disciple of Gautama Buddha.

At the king's request, Kātyāyana left with a group of seven friends to visit the Buddha to invite him to come to Avanti.

There is a famous incident given in Verse 43 of the Dhammapada commentary in which a man named Soreyya was traveling with a friend and happened to see Kātyāyana adjusting his robes.

[7] In the lifetime of Padumuttara Buddha, Kātyāyana made the resolve to attain greatness[2] after hearing the praise of another monk that shared his name.

Instead of the Buddha himself, the newly ordained and enlightened Kātyāyana returned to Avanti to teach King Candapajjota.

Kātyāyana made numerous converts in Avanti, until the land sparkled with monk's robes, the texts say.

[8] Nevertheless, he is said to have travelled to listen to the Buddha's sermons often, to the extent that his fellow disciples regularly left an empty seat for him to sit on.

When Rudrayana's harem was interested to listen to his teachings too, Kātyāyana refused, however, pointing to a prohibition that the Buddha had given in this regard.

As for Rudrayana, after the queen fell ill and died, he wanted to be with her in the afterlife, and decided that ordination as a monk could take him there.

[2] In the Madhura Sutta, King Avantiputta of Madhurā approached Kātyāyana some time after the Buddha's parinirvana with a question regarding the Brahmin's claims to superiority due to their caste.

[citation needed] Tradition also holds that Kātyāyana was the author of some verses of the Theragāthā, where he gives advice to meditators.

[2] In Chapter 3 of the Lotus Sutra entitled "Simile and Parable", Kātyāyana is one of four disciples to understand the Buddha's intention to his sermon about the burning house, and who rejoice in the idea of the united vehicle (ekayāna).

[14] Tradition attributes to Katyāyana the authorship of two late Pāli canonical texts, that is, the Nettipakarana, a commentary on Buddhist doctrine; and the Peṭakopadesa, a treatise on exegetical methodology.