Colonel Gajraj Singh Thapa (Nepali: गजराज सिंह थापा) was the first person to establish tea plantation estates in Nepal.

Around 1873, Thapa, son-in-law of Prime Minister Jung Bahadur Rana, was on a tour of Darjeeling.

[2] Colonel Thapa was then the Governor General (Bada Hakim) of the eastern region of Nepal.

[3][4] Translation of various signposts placed in Ilam (shown below), reads that the very first tea saplings planted by Thapa was received as a gift from the Government of China, it was gifted to his father-in-law prime minister Jung Bahadur Rana.

According to the signpost the genus of tea planted in the estate were Camellia sinensis/Camellia Assamica/Camellia assamica sub sp Lasiocalyx or cambodensis.