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The aim of this study was to analyze the microstructure of cheeses before and after drying using preliminary coloring. The objects of research were cheeses of the following brands: "Pokrovskiy", "Russian" and "Gollandskiy". Drying of cheeses was carried out in a vacuum drying unit at a residual pressure of 7-8 kPa, a heat flux density of 5±0.5 kW/m2, and a heating temperature of 50±1 °C. Photographs of the microstructure were obtained on a scanning electron microscope JEOL JSM-6390 LA. Two methods were used to stain the fat of cheeses before microstructural analysis: Sudan according to Gersheimer; Sudan III and methylene blue. In colored cheeses in any of the ways, in comparison with uncolored cheeses, their structure becomes more clearly visible during electron microscopy. In the structure of cheeses, fatty elements are present in the form of irregular droplets, ranging in size from 30 to 100 microns. It was found that the structure of cheeses stained with Sudan III and methylene blue is clearer and more pronounced in comparison with the structure stained with Sudan III according to Gersheimer. Since fat melting occurs when dyeing dry cheese with Sudan III according to Gersheimer, this technique cannot be used for dyeing fat in dry cheeses. It is recommended to stain the fat in dry cheeses with Sudan III and methylene blue. In stained cheeses, the size of calcium phosphate before drying was determined from 5 to 10 microns, in cheeses after drying from 30 to 100 microns. [ABSTRACT FROM AUTHOR]