"We have recovered 14 bodies of the Maoists from the site of the clash," the officer said, adding that the insurgents might have suffered further casualties.
He said soldiers, backed by helicopters, had fought the rebels for more than six hours in the remote forested hills. There was no comment from the Maoists who want to establish communist rule in the nation, one of the world's poorest.
Authorities have said the rebels could step up violence ahead of next month's ninth anniversary of the start of their revolt, in which more than 11,000 people have been killed so far. Last week, the Maoists killed 23 soldiers in an ambush in a tea-growing area in eastern Nepal.
The insurgency has wrecked an economy dependent on aid and tourism, displaced tens of thousands and threatened the stability of the mountainous nation tucked between Asian giants China and India.