Purpose. Determination of the possibility to diffe­rentia­te triticale samples by starch grain size and identify samples with a minimum size of granules that have a significant positive correlation with the efficiency of the starch transformation into ethanol. Methods. Light mic­roscopy of grinded triticale grains. Results. Analysis of the starch granule size in triticale samples was performed. The minimum average granule size was observed in line Kc-270/14 (23.78 µm), maximum one – in line KR-110/14 (28.06 µm). The size of starch granules in a soft winter wheat variety ‘Tsvit Kalyny’ was 24.2 µm that was within the values typical for winter triticale varieties and lines. The size of the majority of granules ranged from 15 to 35 µm, but their distribution was uneven in the studied lines. Conclusions. Considerable polymorphism of winter triticale for the starch granule size was established. It was found that the minimum average size of starch granules was observed in the samples characterized by minimum maximum size of granules, low frequency of granules of more than 35 µm, and therefore, minimum dispersion. Based on this, assumption can be made about the possibility to evaluate a sample for the presence of granules larger than 35 µm that can significantly reduce the number of measurements and speed up analysis.