Nepal-Sri Lanka established diplomatic relationship on 01 July 1957. As sovereign modern states, Nepal and Sri Lanka enjoy warm and friendly relations based on mutual respect, cooperation and understandings. They work together at the United Nations special agencies as well as Colombo Plan for Cooperative Economic and Social Development in the Asia and Pacific. They hold similar views on most of the international issues, be it in the UN or any other multilateral forums. They are the founder members of the Non-Aligned Movement (NAM) and the South Asian Association for Regional Cooperation (SAARC) and are members of the Bay of Bengal Initiatives for Multi-Sectoral Technical and Economic Cooperation (BIMSTEC) among others. Over the past five decades, the two countries have concluded several agreements and set-up numerous mechanisms to enhance bilateral relations to their mutual benefit.
SOME MILESTONE STEPS TOWARDS STRENGTHENING THE NEPAL-SRI LANKA BILATERAL RELATIONS
| Year | Milestone Steps |
| 1 July 1957 | Establishment of Diplomatic Relations between Nepal and Sri Lanka |
| 1975 | Establishment of Honorary Consulate-General of Nepal in Sri Lanka (it existed until the establishment of Embassy of Nepal in Colombo in 1995) |
| 19 February 1977 | Signing of Air Services Agreement between Nepal and Sri Lanka (it was replaced by a new one in 2009) |
| 03 April 1979 | Signing of Trade Agreement between Nepal and Sri Lanka |
| 1986 | Establishment of Sri Lanka Nepal Friendship Society in Colombo |
| 1989 | Purchase of 1.5 acres of land in Colombo for the Embassy of Nepal |
| 1993 | Establishment of the Sri Lankan Residential Embassy in Kathmandu |
| 11 May 1995 | Establishment of the Nepalese Residential Embassy in Colombo |
| 06 July 1999 | Signing of Cultural Agreement between Nepal and Sri Lanka |
| 06 July 1999 | Signing of the Avoidance of Double Taxation Agreement between Nepal and Sri Lanka |
| 2002 | Establishment of Sri Lanka-Nepal Parliamentary Friendship Association |
| 2002 | Establishment of Sri Lanka Nepal Business Council in Colombo |
| 31 March 2003 | Signing of an MOU between The Ceylon Chamber of Commerce, Sri Lanka and the Confederation of Nepalese Industries (CNI) |
| 20 April 2007 | Signing of an Agreement on exemption of visa fees for students studying in both countries |
| 05 March 2008 | Reconstruction of the Sri Lanka-Nepal Parliamentary Friendship Association |
| 03 March 2009 | Signing of (revised) Bilateral Air Services Agreement |
| 03 March 2009 | Signing of Agreement on the establishment of a Joint Commission at the Foreign Minister’s level |
| 14 March 2010 | Establishment of Sri Lanka Nepal Friendship and Business Council in Colombo |
| 1 October 2016 | Establishment of Direct Air Connectivity by Himalaya Airlines, a Nepalese airlines on Katmandu- Colombo- Katmandu sector (It has been suspended now. Last flight was on 25 March 2017) |
| 16 November 2016 | Revival of Sri Lanka-Nepal Parliamentary Friendship Association |
| 7 February 2017 | Formation of Sri Lanka- Nepal Chamber of Commerce and Industries |
| 22 February 2017 | Sri Lanka -Nepal Business Forum held in Colombo and Signing of an MOU between Nepal-Sri Lanka Chamber of Commerce and Industry and Federation of Chamber of Commerce and Industries of Sri Lanka. |