Primulina modesta is a plant in the family Gesneriaceae, native to Vietnam.

The leaves are dark green above, pale beneath and measure up to 3 cm (1 in) long.

[3] Primulina modesta is endemic to Vietnam, where it is confined to Tam Cung Cave, on an island in Hạ Long Bay, a UNESCO World Heritage Site.

[3] Primulina modesta has been assessed as critically endangered on the IUCN Red List.

The species is confined to a small area and the population has been estimated at fewer than 50 plants.