Śīlabhadra (Sanskrit; traditional Chinese: 戒賢; ; pinyin: Jièxián) (529–645) was a Buddhist monk and philosopher. He is best known as being an abbot of Nālandā monastery in India, as being an expert on Yogācāra teachings, and for being the personal tutor of the Chinese Buddhist monk Xuanzang.
Śīlabhadra was born in the Samataṭa kingdom, in the Brahmin caste, to the royal family there. As a young man he went westward to Nālandā, and was trained there by Dharmapāla of Nālandā, who also ordained him as a Buddhist monk. According to Xuanzang's account, Śīlabhadra gradually became famous for his learning even in foreign countries. At 30 years old, after defeating a Brahmin from southern India in a religious debate, the king insisted on giving him the revenue of a city, which Śīlabhadra accepted with reluctance, and he built a monastery there and kept it funded it with the city's revenues. The name of this monastery was Śīlabhadra Vihāra.
At the age of 33, the Chinese Buddhist monk Xuanzang made a dangerous journey to India in order to study Buddhism there and to procure Buddhist texts for translation into Chinese. Xuanzang spent over ten years in India traveling and studying under various Buddhist masters. These masters included Śīlabhadra, the abbot of Nālandā monastery, who was then 106 years old. Śīlabhadra is described as being very old at this time and highly revered by the monks:
He was then very old, his nephew Buddhabhadra being 70 years of age. The pilgrim was met by twenty grave-looking monks, who introduced him to their chief, the venerable "Treasure of the True Law," whose proper name of Śīlabhadra they did not dare to pronounce. Xuanzang advanced towards him according to the established etiquette on his elbows and knees, a custom which is still preserved in Burma under the name of Shikoh.