The wall painting surfaces represent the main challenge for the laser cleaning techniques. Theobjective of this work has been the study of the laser cleaning technique when applied to wallpaintings. In particular, this study has been devoted to understanding how the characteristics of thelaser apparatus and its specific use are linked with the nature of the substances to be removed fromthe painting. A number of artificially wall paintings were selected with paint layers that werecomposed of different pigments and covered with different dirties. In this work the feasibility of lasercleaning for the removal of dirties from the wall painting surfaces using Q-switch Nd:YAG laseroperating at two different wavelengths: in the infra-red and in the visible (1064 and 532 nm) ispresented. The effectiveness of the cleaning process was monitored by following the disappearancefrom the LIBS spectra of the deterioration aspects elements during successive laser shots. The aimof this work is focus on the definition of the experimental boundary conditions in which laser cleaningcan be safely applied in cleaning of the deteriorated wall paintings.