The visible spectrum of molybdenum in some common welding material and welds is studied by digital analysis. The researches are made on digital processing and analysis technology of Mo438.16nm and Mo481.93nm line groups. The digital analysis method is developed for spectroscopic analysis
of molybdenum in welding material and weld. The results can be used in the qualitative analysis and quantitative analysis on molybdenum in welding material and weld, as well as the material trademark.