Madhuca primoplagensis is a tree in the family Sapotaceae. It grows up to 20 metres (66 ft) tall, with a trunk diameter of up to 35 centimetres (14 in). The bark is dark brown. Inflorescences bear up to 13 flowers. The fruits are ellipsoid, up to 3 centimetres (1 in) long. The specific epithet primoplagensis is from the Latin meaning "first region", referring to Sarawak's First or Kuching Division, the tree's only known home. Its habitat is lowland forests from sea-level to 300 metres (980 ft) altitude. M. primoplagensis is endemic to Borneo and known only from Sarawak.