Mantophryne louisiadensis is a species of frog in the family Microhylidae.

[1][2] It is endemic to Rossel Island, a part of the Louisiade Archipelago in the Milne Bay Province of Papua New Guinea.

[3] Mantophryne louisiadensis occurs in lowland rainforest and cloud forest at elevations below 700 m (2,300 ft).

There are no recent observations of this species, but it does not appear to be facing major threats.

Suitable habitat appears to be plentiful as Rossel Island is very largely covered by primary or slightly disturbed rainforest and this species ranges across the entire altitudinal range of the island.