Figures released by the immigration office at Tribhuvan International Airport in Tibet reveal tourist arrivals reached 35,330 in January 2013, a decline of 15.9 per cent on the same month last year.
Major source markets have all seen numbers of tourist arrivals fall in the first month of 2013.
In the SAARC region only Pakistan has recorded positive growth - up 5.8 per cent.
India, which constitutes the major market of Nepal, has recorded negative growth of 26.1 per cent.
Arrivals from Bangladesh and Sri Lanka have also registered negative growth by 62.6 per cent and 42.6 per cent respectively.
Arrivals from Asia (other than south Asia) have also recorded negative growth of 16.4 per cent in aggregate with mixed results.
Visitor arrivals from China have decreased by 40.3 per cent.
However, the arrivals from Japan, Singapore, Thailand, Malaysia and South Korea all increased by 16.8 per cent, 10.3 per cent, 4.3 per cent, 42.6 per cent and 11.2 per cent respectively.
A total of 45,667 foreign tourists departed from TIA in January 2013.
The number of Nepalese arrivals stood at 69,442 while 91,281 Nepalese departed from TIA in January 2013.