A coated layer at the surface of cooked rice grain was visualized using a simple sectioning method, fluorescence microscopy, and digital image processing. Polished rice grain (150 g) was added to 150, 225, or 300 ml of water, which was 1.0×, 1.5×, or 2.0× (w/w) the weight of the grain, respectively. The rice was cooked and then examined. The sections of whole size grain obtained by the simple ... [Show full abstract] sectioning method were captured using a stereomicroscopy with transmission and fluorescent modes. The actual grain section including the coated layer was observed in the transmission image. In contrast, the cell morphology in the grain, which showed the exact size of the sectioned grain, was visualized in the fluorescence image. The composite image of both the fluorescent and transmission images captured at the same position can show extra portions of the actual section, which can be distinguished from the morphological tissue area and regarded as the coated layer. The specific layer thicknesses estimated from the composite images shown in this report were approximately 1–7 μm, which increased with increasing amount of cooking water. Differences in the layer thickness at the dorsal and ventral sides were also observed.