Abstract: The theory of 'lucid waters and lush mountains are invaluable assets' raised by President Xi Jinping, is an important part of the theory of ecological civilization of socialism with Chinese characteristics. This theory is the centralized embodiment of the Marxism in China featured by the harmonious relations between human and nature. It is also the essentialembodiment of green development pattern transformation in contemporary China. This paper attempts to contribute to the theory by analyzing practical significance of this theory to construct ecological civilization in China. Challenges of practicing this theory were analyzed from four aspects, including ecological environment's quality, transformation channel from 'lucid waters and lush mountains' to 'invaluable assets', construction of institutional system, and mechanism of benefit guidance. As a result, this paper proposed five mechanisms to promote the practical value of this theory. (1) Establishing protection mechanism to maintain good ecological foundation by protecting and repairing ecosystems, solvemain environmental problems, and strengthen the space control of ecological environment. (2) Establishing transformation mechanism by opening the transformation channel from lucid waters and lush mountains toinvaluable assets by developing ecological economy based on ecological advantages, and cultivating new kinetic energy of green development. (3) Establishing accountability mechanism with setting up strict system to implement government responsibility of protecting ecological environment, to implement enterprise responsibility ofcontrollingenvironmental pollution, and to promote public to protect lucid waters and lush mountain. (4) Establishing ecology accounting mechanism by compiling the balance sheet of natural resources, continue to promote green GDP accounting, and carry out ecological assets accounting. (5) Establishing feedback mechanism from 'lucid waters and lush mountains' to 'invaluable assets' with the system of paid use of natural resources, ecological compensation system, and green financial system.