So far five bodies have been recovered in two settlements near Houailou on the main island's east coast where about 400 millimetres of rain fell in 12 hours.
Three people are still missing and eight others have been injured.
The villages of Gouareu and Ouakaya were hit by the landslides which came off a mountain range which the mayor of Houailou Pascal Sawa said had been weakened by nickel mining and bush fires.
The area was considered to be at risk after major slips in 2008 and 2011.