Mobile Laser Scanning (MLS) systems have become an indispensable solution that has reached a high level of popularization in various fields, for instance, digital twinning, smart cities, engineering geodesy, 3D modeling, autonomous driving, etc. Compared with the remarkable achievements of the MLS systems in efficient data acquisition and various scenario applications, the uncertainty evaluation and reduction has not followed the same trend, significantly lagging behind the development pace of current MLS systems. On the other hand, uncertainty-aware digital twinning remains an underexplored topic. This talk will present our latest work on modeling uncertainty in MLS point clouds and its application to building quality-assured urban digital twin.