Mastixia glauca is a tree in the family Nyssaceae. The specific epithet Greek, Modern (1453-);: glauca is from the Greek meaning "bluish-grey", referring to the colour of the leaf underside.
Mastixia glauca grows as a tree measuring up to 15m (49feet) tall with a trunk diameter of up to 25cm (10inches). The pale green fruits are oblong-ovoid and measure up to 40NaN0 long.
Mastixia glauca is endemic to Borneo and confined to Malaysia's Sarawak state where it is known only from Mount Santubong. Its habitat is mixed dipterocarp forests at around 100m (300feet) altitude.