Comprehensively evaluating the accuracy of the digital elevation model (DEM) upscaling methods is significant for us to choose the DEM upscaling method reasonably, master the DEM upscaling law, and construct a new DEM upscaling model. However, the current researches on DEM accuracy evaluation are still not sufficient to meet the requirements of practical applications. In this paper, an accuracy assessment method for DEM based on energy factor is proposed and then is applied to the accuracy assessment of different DEM upscaling methods. A comprehensive evaluation strategy combining qualitative and quantitative accuracy assessment and quality evaluation methods is constructed to verify the rationality and effectiveness of the assessment strategy based on energy factor. The experimental results show that the accuracy assessment method based on energy factor is simple in theory and is easy to operate in practice. It can reflect the retention characteristics of the terrain masking relationship of the upscaling methods, whereas the traditional precision evaluation strategy cannot reflect them directly. This accuracy assessment framework also provides a new and valuable standard for choosing the DEM upscaling methods, and puts forward new design requirements for the DEM upscaling methods. It also has great influence on remote sensing modeling and inversion.