Autoclaved aerated concrete (AAC) masonry blocks are construction material with high heat insulation parameters. In time of sustainable construction, this material can be used as a load bearing construction material for a range of buildings where it is necessary to obtain high heat insulation parameters of external delimiting constructions. The main problem of AAC masonry constructions is the significant influence of moisture content and its gradient on heat resistivity properties of the AAC. It is important to monitor the drying process of AAC masonry constructions in order to avoid sealing of moisture inside the masonry by early application of finishing layers on the construction. Therefore, EIS method for detection of moisture distribution throughout the cross section of AAC masonry constructions in situ conditions has been applied.