At least 18 people were killed Tuesday afternoon in Achham district, said Thir Bahadur Gharti Chhettri, an official at the Disaster Management Section of the Home Ministry.
Four members of a family were also killed in Thapakhana village in Parbat district late Tuesday night, he added.
Earlier Tuesday morning another 12 people were buried under landslides in Mastamandu village in Dadeldhura district. The landslide-prone area is about 480 miles (775 kilometers) west of Katmandu.
Few other details were immediately available from the remote area, officials said.
Heavy rains have paralyzed much of western Nepal over the past four days.