[Objective] The value of ecological products was calculated scientifically and the transformation path of “Two Mountains” (lucid waters and lush mountains are invaluable assets) was explored in order to provide theoretical support for the practical effect of the “Two Mountains” theory and promote the construction of an ecological civilization. [Methods] Based on the theory of “Two Mountains,” and taking Guizhou Province as the research object, this paper constructed an index system of ecological product value accounting, measured the ecological product value using the gross ecosystem production (GEP) accounting method, and assessed the effect of the “Two Mountains” transformation. [Results] ① From 2017 to 2021, the GEP of Guizhou province showed an upward trend, which was 2.08~2.54 times the GDP of the same year, but the growth rate of the GEP was lower than that of the GDP. The GEP per unit area was 1.96×10⁷ yuan/m² to 2.32×10⁷ yuan/m², and the per capita GEP was 90 500 yuan/m² to 1.06×10⁶ yuan/m². The results showed that the transformation of environmental resource protection, sustainable utilization, and the economic growth mode has achieved certain results. ② The value of ecological material supply products presented an upward trend with a range of 18.66%; the value of agricultural products was the highest and the value of fishery products was the lowest. The results showed that Guizhou is still a province with agriculture as its main focus, and planting is the main aspect of the agricultural industry. ③ The total value of ecological regulation service products showed an increasing trend, with an increasing range of 8.34%, accounting for 60.30%—66.35% of the GEP. The value of climate regulation was the highest, and the value of water quality purification was the lowest. This shows that a superior ecological environment and high forest coverage are important climate regulators and ecological barriers. ④ The value of eco-cultural service products (ECVs) showed an increasing trend, with an increasing range of 45.71%, accounting for 20.56%—27.65% of the GEP. ⑤ The transformation value of “Two mountains” showed an increasing trend of dynamic change, with an increasing range of 39.37%, accounting for 82.40%—92.40% of the GDP. This shows that the “Two Mountains” transformation has achieved certain results, and the contribution of ECVs has been high. However, Guizhou Province needs to further enhance the effectiveness and contribution of eco-material product value and eco-cultural product value in the process of the “Two Mountains” transformation. Based on the research results, this paper refines the path to promoting the “Two Mountains” transformation. [Conclusion] The protection effect of natural resources and ecological environment in Guizhou Province is increasing, the ecosystem has strong ecological regulation function, and climate regulation is the main type of ecological regulation; The value of non-physical products is dominant, and the value of physical products is relatively small. The transformation effect of “Two Mountains” is increasing year by year, however, it is necessary to further improve the contribution of the value of ecological material products and ecological culture products to the transformation of “Two mountains”.