In Vajrayana Buddhism, the Womb Realm (Skt. garbhakosa-dhatu, Japanese: 胎蔵界 taizōkai) is the metaphysical space inhabited by the Five Wisdom Kings. The Womb Realm is based on the Mahāvairocana Sutra. The name of the mandala derives from chapter 2 of the sutra, where it is said that Mahāvairocana Buddha revealed the mandala's secret teachings to his disciple Vajrasattva from his "womb of compassion". In other translations, the term matrix realm or Matrix Mandala are used.
The Womb Realm is a very popular subject for mandalas, and along with the Diamond Realm (vajradhatu) Mandala forms the Mandala of the Two Realms. This mandala, along with the Diamond Realm, form the core of Japanese esoteric, or Shingon Buddhist, rituals, including the initiation or abhiseka ritual. In this ritual, new initiates are blindfolded and asked to toss a flower upon a mandala. Where the flower lands helps decide which Buddhist figure the student should devote themselves to.
In traditional Shingon halls, the Womb Realm Mandala is hung on the east wall, symbolizing the young stage of Mahāvairocana Buddha.In this setting, the Diamond Realm Mandala is hung on the west wall symbolizing the final realization of Mahāvairocana Buddha.
Womb Realm map 
See also 
- Abe, Ryuichi (1999). The Weaving of Mantra: Kukai and the Construction of Esoteric Buddhist Discourse. Columbia University Press. ISBN 0-231-11286-6.
- Hakeda, Yoshito S. (1972). Kūkai and His Major Works. Columbia University Press. p. 26. ISBN 0-231-05933-7.
- Hakeda, Yoshito S. (1972). Kūkai and His Major Works. Columbia University Press. p. 44. ISBN 0-231-05933-7.
- Hakeda, Yoshito S. (1972). Kūkai and His Major Works. Columbia University Press. p. 87. ISBN 0-231-05933-7.
- Mandala of the Womb World Japan, Kamakura period, 13th - 14th century Dharmapala Thangka Centre
- The Diamond and Womb World Mandalas Dharmapala Thangka Centre