Customs:

All baggage must be declared and cleared through the customs on arrival at the port of entry. Passengers arriving at Tribhuvan International Airport (TIA) without any dutiable goods can proceed through the Green Channel for quick clearance without a baggage check. If you are carrying dutiable articles, you have to pass through the Red Channel for detailed customs clearance.
Imports:

Apart from used personal belongings, visitors are allowed to bring to Nepal free of duty cigarette (200) or cigars (50), distilled liquor (one 1.15 liter bottle), and film (15-rolls). You can also bring in the following articles free of duty on condition that you take them out with you when you leave: binoculars, movie or video camera, still camera, laptop computer, and portable music system.
Export:

It is illegal to export objects over 100-years old sacred images, paintings, manuscripts that are valued for culture and religious reasons. You are advised not to purchase such items are Nepal’s cultural heritage and belong here. The Department of Archaeology has to certify all metal statues, sacred paintings and similar objects before they are allowed to be sent or carried out of the country. Handicraft dealers and travel agents are able to assist you in this process.