Synthesizing and studying the properties of nanomaterials based on layered molybdenum disulfide, often face a need for rapid elemental analysis and prompt return of the material to the customer. Sometimes, nanoparticles of molybdenum disulfide are to be modified with metal compounds to improve the catalytic or magnetic properties of the material. We propose a method for rapid X-ray fluorescence determination of molybdenum and cobalt in the range of 10 – 50% in such compounds using a bulk method without dilution. Analytical signals were measured at the wavelengths of MoKα and CoKα lines using a VRA-30 spectrometer (Carl Zeiss, Germany; X-ray tube with Rh anode). The metal content was calculated using the derived coupling equations. The determination error ranges within ±2.7% (abs.) and 1.4% (abs.) for Mo and Co, respectively. Correctness of the method was confirmed for a batch of synthesized compounds by comparison of the results obtained with the data of XRF analysis using the dilution method traditionally used in the laboratory. The proposed rapid method provides simplification of the procedure and more than 4-fold shortening of analysis in time, the sample being preserved and can be used for further research.