As clay minerals complex with high reactivity, Fe-Mn nodules in soil, with special geochemical characteristics, different from Fe-Mn nodules in the ocean, can always be found in drying-wetting cycle condition and water-air disturbing environment. Fe-Mn nodules, the new-formed component in the pedosphere, appear the various qualities in different regions. The investigation on adsorption behavior between soil Fe-Mn nodules and metals in the representative areas is helpful to understand further the micro-ecological property of Fe-Mn nodules and is significant for soil exploitation and utilization, conservation and improvement, and contamination remediation. It currently lacks the related research on soil Fe-Mn nodules in western China, while this paper might supply unclear information and improve the research level from a spectral aspect. Water-washing method was used and spectral analysis approaches of Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES), Ultraviolet-Visible Spectroscopy (UV-Vis), X-Ray Diffractometer (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) were applied to analyze the main elemental oxides and structure of Fe-Mn nodules in western China. Batch adsorption procedures were involved in study the reaction, and the effects of time, cadmium concentration and temperature were discussed. The kinetics equation and isotherms equations were used to fit the reaction, thermodynamic parameters were calculated, and the desorption experiments were studied. The dominant elemental oxides include Fe₂O₃, SiO₂, Al₂O₃ and MnO, with the highest content of Fe₂O₃ followed by SiO₂ in Fe-Mn nodules. Similar mineral components are found between Fe-Mn nodules and soil samples, and functional groups of —OH, Si—O—Si (Al) and Fe(Mn)—O appear in the FTIR spectrum. The adsorption is fast at the beginning of the reaction and then becomes slow gradually. The adsorption capacity (Q) reaches 4.96 mg·g^-1 at 6 h, and changes little after 12 h. The increased concentration of cadmium leads to higher Q values, and temperature affects little the reaction. Pseudo-second order equation fit better with a higher coefficient of R² (0.994 3), indicating the reaction rate might be controlled by chemical adsorption. The value of R² (0.999 1) from the Langmuir equation, is higher than that from the Freundlich equation, suggesting the reaction belongs to the monolayer chemical adsorption. The reaction is spontaneous and endothermic, and complexation might be involved during the process. Positive S value suggests an increase in randomness during the interaction. The desorption efficiency is better with HCl solution (0.1 mol·L^-1, prepared with tap water). The research is significant for mechanism analysis with spectral approaches in future.