The Chang’E-1 Laser Altimeter(LAM), as one of the scientific instruments onboard the Chinese Chang’E-1 orbiter, has successfully gained the massive lunar elevation scientific data of global topography of the moon. Uncertainty evaluation of the lunar elevation detection error based on LAM scientific data is developed in this paper. Firstly, the data are selected from the flat terrain region in all the lunar elevation detection data; Secondly, after the pseudo elevation data are removed in the selected region, regional elevation mean and standard deviation are calculated. Making use of the calculations and taking into account all kinds of uncertainty contributors of LAM orbiting exploring, the uncertainty evaluation methods of the LAM in-orbit elevation exploring are proposed on the basis of the guide to Monte Carlo Methods. Finally, the uncertainty evaluation results of different regions of lunar surface are given. The evaluation results not only can provide the basis for further analysis laser altimeter measurement error sources, but also give the reference for making the high precision moon digital elevation graph and provide theoretical guidance for the accuracy requirement of design of payload on lunar orbiter.