Maheśvara (Sanskrit: महेश्वर; Pali: Mahissara; traditional Chinese/Japanese: 大自在天; Pinyin: Dàzìzàitiān, Rōmaji: Daijizaiten) is a deva in Buddhist mythology.

Present Maheśvara is Buddhist by religion, and was reborn as a Deva, because of his merit of donating a cup of honey to Kassapa Buddha in one of his previous lives.

[citation needed] A popular story tells how Vajrapāni kills one Maheśvara, because of his evil deeds.

The story begins with the transformation of the bodhisattva Samantabhadra into Vajrapāni by Vairocana, the cosmic Buddha, receiving a vajra and the name "Vajrāpani".

Vajrapāni refuses because Maheśvara "is deluding beings with his deceitful religious doctrines and engaging in all kinds of violent criminal conduct".