The Prashna Upanishad (Sanskrit: प्रश्न उपनिषद्, Praśna Upaniṣad) or the Prashnopanishad (Sanskrit: प्रश्नोपनिषद्‍, Praśnopaniṣad) is one of the earlier, "primary" Upanishads commented upon by Shankara. It is a Mukhya Upanishad, associated with the Atharvaveda. It figures as number 4 in the Muktika canon of 108 Upanishads.

In Sanskrit, "Prashna" means question. This text consists of six questions and their answers, hence the name. It is in the form of questions and answers. Except the first and the last questions, all other questions are actually a group of smaller sub-questions.

As narrated in the beginning of this Upanishad, Six pupils interested in knowing divinity or Brahman come to sage Pippalada and request him to clarify their spiritual doubts. Instead of answering immediately, Pippalada asks them to take up penance and Brahmacharya for one year at his place. Upon completion of one year, pupils ask the sage, then the sage answers their questions.

The pupils who asked the questions were: