Niō (仁王) are two wrathful and muscular guardians of the Buddha standing today at the entrance of many Buddhist temples in East Asian Buddhism in the form of frightening wrestler-like statues. They are dharmapala manifestations of the bodhisattva Vajrapāṇi, the oldest and most powerful of the Mahayana Buddhist pantheon. According to scriptures like the Pāli Canon as well as the Ambaṭṭha Sutta, they travelled with Gautama Buddha to protect him. Within the generally pacifist tradition of Buddhism, stories of dharmapalas justified the use of physical force to protect cherished values and beliefs against evil. They are also seen as a manifestation of Mahasthamaprapta, the bodhisattva of power that flanks Amitābha in Pure Land Buddhism and as Vajrasattva in Tibetan Buddhism.

A dharmapāla is a type of wrathful god in Buddhism. The name means "dharma protector" in Sanskrit, and the dharmapālas are also known as the Defenders of the Justice (Dharma), or the Guardians of the Law. There are two kinds of dharmapala, Worldly Guardians (lokapala) and Wisdom Protectors (jnanapala). Only Wisdom Protectors are enlightened beings.