The Mahapuranas are a collection of eighteen foundational Hindu texts that preserve mythology, philosophy, cosmology, sacred geography, genealogies, ritual traditions, and teachings on dharma. Composed and expanded over many centuries, they played a central role in shaping popular Hinduism by making religious ideas accessible through stories of gods, sages, kings, and devotees. Together, the Mahapuranas form one of the largest and most influential bodies of literature in the Hindu tradition.

The term "Mahapurana" means "Great Purana." These eighteen texts are traditionally regarded as the principal Puranas and are distinguished from the many smaller Upapuranas, or minor Puranas, which focus on more specific deities, regions, or traditions. While all Mahapuranas are Puranas, not all Puranas are Mahapuranas.