Yajnavalkya or Yagyavalkya is a Hindu Vedic sage featuring in the Brihadaranyaka Upanishad. Yajnavalkya proposes and debates metaphysical questions about the nature of existence, consciousness and impermanence, and expounds the epistemic doctrine of neti neti to discover the universal Self and Ātman. Texts attributed to him include the Yajnavalkya Smriti, Yoga Yajnavalkya and some texts of the Vedanta school. He is also mentioned in various Brahmanas and Aranyakas.

The Brihadaranyaka Upanishad is one of the Principal Upanishads and one of the first Upanishadic scriptures of Hinduism. A key scripture to various schools of Hinduism, the Brihadaranyaka Upanisad is tenth in the Muktikā or "canon of 108 Upanishads".