In Jainism, a Nirgranth Sadhu refers to a Jain monk who has renounced all worldly possessions and attachments. The term "Nirgranth" literally means "one who is free from all bonds or knots (attachments)," and "Sadhu" means an ascetic or monk.

Nirgranth Sadhus strictly follow the five great vows (Mahavratas):

1. Ahimsa (non-violence)
2. Satya (truthfulness)
3. Asteya (non-stealing)
4. Brahmacharya (celibacy)
5. Aparigraha (non-possession)

They lead a life of austerity, practicing self-discipline, meditation, and spiritual study, and depend on alms for sustenance. The founder of Jainism, Lord Mahavira, was often referred to as "Nirgranth" because of his complete renunciation. His followers, the Jain monks, are also called Nirgranth Sadhus, especially in ancient Jain texts.