The treatment of rising damp in historical buildings walls is very complex. Moisture transfer in walls of old buildings, which are in direct contact with the ground, leads to a migration of soluble salts responsible for many building pathologies. The present work describes an extensive numerical analyse of rising damp phenomenon, using the software WUFI-2D, developed by Fraunhofer Institute for Building Physics. The results show that the numerical simulation describes very well the rising damp front for different boundary conditions and materials. The influence of the wall thickness, boundary conditions, composition of walls and material properties, such as, porosity and water absorption coefficient were analysed in detail.