In laboratory tests a method was developed for a non-contacting moisture gauging on conveyor belts of different materials like coal, clay, industrial slay and stones of inflating clay. The moisture was measured with an241Am-Be-neutron source, the absolute necessary determination of the changing flow of material was made with the gamma rays of137Cs or241Am. The analysis of the records shows, that to all measuring values mathematical defined curves could be found, so that methods of calculation for the moisture content could be deduced. The maximal obtainable accuracy is about ±0.5 percentage by weight. With the industrial slay and the stones of inflating clay supplementary tests were made direct on the conveyor bell. They shows, that also in the practice good results can be obtained.