Son of Mahādāṭhika and King of Sri Lanka for nine years and eight months. His younger brother, by whom he was ultimately slain, was Kanirajānu-Tissa, and he had two children, a son Cūḷābhaya and a daughter Sīvalī. Iḷanāga was his nephew.

Āmaṇḍagāmani heightened the cone of the Mahā Thūpa and made additions to the Lohapāsāda and the Thūpārāma. He also built the Rajatalena-vihāra and the Mahāgāmeṇḍi reservoir to the south of Anurādhapura, which latter he gave for the use of the Dakkhiṇavihāra.

He enacted an order that there should be no slaughter of animals in Sri Lanka and had gourds planted everywhere. To the whole brotherhood of monks in the island he once gave robes and alms-bowls filled with kumbhandaka fruits (pumpkins) and thereafter he was known by the name of Āmaṇḍagāmaṇī (Āmaṇḍa is evidently a synonym of Kumbhaṇḍaka).

His brother Kanirajānu-Tissa, having killed him, succeeded to the throne (Mhv.xxxv.1-10; MT.640). Āmaṇḍagāmaṇī is also referred to as Āmaṇḍa and Amaṇḍiya.