The unique natural environment of the Qinghai-Tibet Plateau has restricted the construction and function of its transportation infrastructure. In order to evaluate the traffic facilities on the Qinghai-Tibet Plateau, taking Linzhi City, a typical area of southeastern Tibet with high altitude and uneven terrain, as an example and considering the natural characteristics, various transport modes, transport stability, and location advantage, this study established an evaluation system of comprehensive traffic advantage degree to empirically examine the situation in 2015 and 2020. The results show that: 1) Bayi District, Milin County, and Gongbujiangda County, especially their central towns, have much higher scores in internal traffic function, external traffic function, and location advantage degree, while the values of traffic advantage and many of its indicators in Chayu County and Motuo County are low, and the impact of some key transportation infrastructures such as the G318 Highway (national highway), Linzhi-Lhasa Highway, and Milin Airport is prominent. 2) The results of spatial difference analysis show that the comprehensive traffic advantage degree of Linzhi City is unbalanced, and the county-level gap and spatial polarization effect tend to increase. However, the core-periphery spatial structure is fragmented and interrupted by terrain factors of extreme difference in altitude, and the border area of Linzhi City becomes the weakest part with regard to the comprehensive traffic advantage degree. 3) There is a certain degree of matching between the comprehensive traffic advantage degree and the population distribution as shown by the linear trend line and coupling coordination relationship. Bayi District, Milin Town, and Gongbujiangda Town have reached the high-quality coordination level. However, most of the towns are at the preliminary or intermediate coordination level, while in the border area and areas with severe natural constraints, the coordination degree urgently needs to be optimized. Methodologically, by superimposing regional natural attributes, expanding the evaluation dimension of traffic advantage degree, and integrating various modes of transportation, the comprehensive traffic advantage evaluation conforms to the actual situation of the study area. Regional transport evaluation that incorporates the consideration of natural environment characteristics has practical significance for supporting territorial planning and transportation infrastructure evaluation and management, especially for regions such as the Qinghai-Tibet Plateau.