[Objective] Based on the improved unit area ecological service value and land cover data set, the evolution of the ecosystem service value of the Qinghai-Tibet Plateau from 1992 to 2015 was evaluated. Aims included providing spatial guidance for the ecological security of the Qinghai-Tibet Plateau.[Methods] We applied the improved value equivalent factor in combination with CCI-LC long-term sequence land cover data to assess ecosystem service values.[Results] ① The value of the ecosystem services on the Qinghai-Tibet Plateau increased form 1992 to 2015, with an increase of 1.62×10¹¹ yuan in 24 years. The values of services of different ecosystem types were ranked:grassland > water area > forest > farmland > wetland > desert. ② The highest value type was the ecosystem regulation service in 2015, which reached 5.53×10¹² yuan, whereas the values of support service and supply service were 1.33×10¹² yuan and 5.50×10¹¹ yuan, respectively, and the cultural service was of least value at 2.90×10¹¹ yuan. ③ The ecosystem service value was affected by elevation and slope, whereby the highest value was in the range of 4 000~5 000 m elevation and 5°~15° slope.[Conclusion] The total value of the ecosystem services in the Qinghai-Tibet Plateau increased from 1992 to 2015, and the value of different ecosystems and ecosystem service types varied greatly. Terrain conditions affected the value of ecosystem services.