The Mandala of the Two Realms (Traditional Chinese: 両界曼荼羅; Pinyin: Liǎngjiè màntúluó; Rōmaji: Ryōkai mandara), also known as the Mandala of the Two Divisions (Traditional Chinese: 両部曼荼羅; Pinyin: Liǎngbù màntúluó; Rōmaji: Ryōbu mandara), is a set of two mandalas in East Asian Esoteric Buddhism, particularly prominent within Chinese Esoteric Buddhism as well as the Shingon and Tendai traditions of Japanese Buddhism. The Dual Mandala comprises two complementary mandalas: the Womb Realm Mandala (Sanskrit: garbhakoṣadhātu, Traditional Chinese: 胎蔵界曼荼羅; Pinyin: Tāizāngjiè màntúluó; Rōmaji: Taizōkai mandara) associated with compassion and the Vajra Realm Mandala (Sanskrit: vajradhātu, Traditional Chinese: 金剛界曼荼羅; pinyin: Jīngāngjiè màntúluó; rōmaji: Kongōkai mandara) associated with wisdom. The Dual Mandalas represent distinct yet non-dual dimensions of the enlightened cosmos centered on the universal Buddha Mahāvairocana (Chinese: 大日如來; pinyin: Dàrì Rúlái; rōmaji: Dainichi Nyorai).

The Mandala of the Two Worlds encapsulates the cosmology, metaphysics, and soteriology of East Asian Esoteric Buddhism. It provides both a visual and ritual method for realizing the practitioner's inherent identity with the Buddha, through the integration of compassion and wisdom. It is thus a symbolic teaching device, a meditative tool, and a ritual instrument. The Dual Mandalas portray two complementary dimensions of Buddhahood. The Womb Realm represents the great compassion (maha karuṇā) of the original Buddha Mahāvairocana who is always nurturing all beings toward enlightenment. The Vajra Realm signifies the indestructible omniscient wisdom (sārvajñana) of Mahāvairocana Buddha which pervades all phenomena. Thus, the Two Worlds Mandala provides a complete map of the cosmos as a unified field of compassion and wisdom which is used by an esoteric practitioner, through ritual and meditative identification with the deities of the mandalas, to progressively actualizes their own original enlightenment.

Both mandalas present highly systematized arrays of buddhas, bodhisattvas, wisdom kings, and celestial beings. The number of deities arranged around the cores varies, but may range as high as 414. Each figure holds specific mudrās (hand gestures) and attributes, and is associated with specific seed syllables (bīja). Both mandalas are oriented according to the cardinal directions, with symbolic meaning attached to each direction. Specific colors are also employed symbolically, representing particular virtues, or elements.

Japanese Shingon and Tendai temples often prominently display the Mandalas of the Two Realms mounted at right angles to the image platform on the central altar. The two mandalas are believed to have evolved separately in India, and were joined for the first time in China, perhaps by Kūkai's teacher Huiguo (746–805).

The conceptual and textual foundations of the Two Worlds Mandala derive from Indian Esoteric Buddhism (Mantrayāna), specifically from two seminal scriptures: the Mahāvairocana Sūtra and the Vajraśekhara Sūtra. Both texts represent advanced stages of Buddhist tantric development in India, reflecting sophisticated ritual systems, mantra theory, and visualization practices intended to rapidly actualize the practitioner's identity with the cosmic Buddha.

The Great Compassion Womb Realm Mandala is primarily based on the Mahāvairocana Sūtra (Chinese: 大日經; pinyin: Dàrì jīng; rōmaji: Dainichi kyō), while the Vajra-realm Mandala is based on the Vajraśekhara Sūtra (Chinese: 金剛頂經; pinyin: Jīngāngdǐng jīng; rōmaji: Kongōchō kyō). The Mahāvairocana Sūtra is said to have been compiled around the mid-7th century in India. Its first chapter provides a Madhyamaka like teaching on emptiness. On the other hand, the Vajraśekhara Sūtra is a compilation of several works, compiled in India beginning at the end of the 7th century. It's orientation is closer to Yogacara Mind-only Buddhism and buddha-nature thought. These sutras draw on previous Mahayana iconography and deities to develop a much more complex esoteric ritual complex. While the Mahāvairocana Sūtra and the Vajraśekhara Sūtra both take Mahāvairocana Buddha as their central theme, they are scriptures of different lineages, composed independently at different times and in different regions of India, and transmitted separately to China.

In Buddhist India, mandalas were often earthen platforms or designs on the ground with cow dung or clay, along with paint or colored powder used for esoteric rituals. They represented the true nature and pattern of all reality as well as the enlightened wisdom of the Buddhas. In China, these designs evolved into permanent paintings or textiles. In some cases, an entire temple complex could be a mandala. Perhaps the most famous example of such a large scale mandala is the Indonesian Buddhist site of Borobudur.

The tradition of laying out Buddhist deities in a sacred diagram (i.e. a mandala) corresponding to the main cardinal directions is not unique to esoteric Buddhist texts. These diagrams first appear in Mahayana sutras like the Sutra of Golden Light (c. 5th century) and the Sukhāvatīvyūha Sūtra. The Golden Light Sutra describes a mandala with Shakyamuni in the center, surrounded by Ratnaketu (south), Amitayus (west), Dundubhisvara (north) and Aksobhya (east) Buddhas. According to Orzech and Sørensen "The Buddhist cave-temples of Kanheri and at Ellora in the Deccan contain what may be the earliest extant examples of rudimentary mandalas in the form of geometric matrices containing Buddhist divinities."