The landslides struck the villages near the resort town of Pokhara, 125 km (77 miles) west of Kathmandu shortly after midnight.
In the village of Lumle about half of the homes were buried or destroyed by a torrent of mud and rocks.
"I heard a big demonic sound, I thought it was an earthquake," said Kabi Ram B.K., a 64-year-old farmer, whose daughter and granddaughter were killed when the landslide smashed into their home.
Soldiers and policemen, working in heavy rain, used shovels and food bowls to search for nine missing villagers because they did not have any mechanical gear to help with the rescue.
At least 13 bodies recovered from the village were laid out on straw matting, covered by a plastic sheet and rug to protect them from the rain.
Lumle is about 15 km (9 miles) from the start of the Annapurna Circuit, a hiking route around the world's 10th tallest mountain that attracts around 100,000 tourists a year.
Two powerful earthquakes in Nepal this year that killed almost 9,000 people have raised the risk of landslides across the mountainous country during the rainy season, which lasts from June to September.
Heavy monsoon rains have also caused flooding and fatalities across northern India in recent days.
Reporting by Aisling Curtis in New Delhi, Jatindra Dash in Bhubaneswar. Editing by Andrew MacAskill and Robert Birsel.
