Suresh Singh Kushbaha, 45, of Madhya Pradesh was arrested at Biratnagar Airport, police officials said.
Police seized 150 notes of Rs 1,000 denomination and 200 notes of Rs 500 denomination from Kushbaha. Both denominations are currently banned in Nepal.
Kushbaha was arrested from the airport before boarding a Buddha Air flight to Kathmandu, airport security chief Sub-Inspector Kumar Shrestha was quoted as saying by the local media.
He was sent to the District Police Office at Morang for "investigation and necessary action".