The ＂Golden Triangle＂, a mountainous area overlapping Thailand, Myanmar and Laos, has been an opium-producing region since the 1920s. Today, Myanmar has still been the second largest producer of opium in the world, after Afghanistan. However, the extensive landscape of opium production has significantly changed in the northern Thai border area of Golden Triangle. Rather than plantations of poppy seeds, north Thai border areas now farm different cash crop plantations, including vegetables, fruits, tea, coffee and rubber. The significant landscape transformation from opium poppy fields to other cash crops plantations results from the international agricultural transfer of the Thai Royal Project. The Thai government recognizes Taiwan as the country that has most successfully transferred its crops and agricultural techniques to the north Thai border area. Nevertheless, Taiwan's participation in the transfer of crops and agricultural techniques was not been for the Royal Project per se, as it was intended to help a specific group of Yunnanese Chinese that fought the Communist Party for the Kuomintang (KMT) during the civil war in China. Restated, many of these Yunnanese Chinese came to north Thai border areas as soldiers of the military troops of Taiwan. Therefore, this essay traces the historical processes of agricultural transfer from Taiwan to the northern Thai borderlands. This essay draws on the historical trajectory to elucidate how the agricultural transfer was not just a mission to erase opium production, but also a geopolitical project to turn the KMT soldiers of Yunnanese Chinese into farmers of Thai citizens. Theoretically, territory is regarded as a more-than-human technology. Therefore, this work uses tea to illustrate the relationship between the international agricultural transfer and the enhancement of the Thai government's control over its north border areas. Additionally, we argue that this political territorialization process also involves an economic deterritorialization, which is realized by turning the former KMT soldiers into modern tea farmers.