The paper presents the results of creating a material for obtaining an early ripening variety of fiber flax for cultivation in Siberia, characterized by high-quality fiber and a high degree of adaptability to external environmental factors, resistance to lodging and diseases. Twelve promising hybrids were studied, the maternal lines of which were represented by Tomsk varieties Tomskiy 16, Tomskiy 17, Tomskiy 18 and TOST 5, and the paternal lines – by Belgian selection varieties Marilyn, Suzanne and Hermes. Field studies were carried out in the subtaiga zone of Tomsk region and were preceded by spring and winter grain crops. Natural and climatic conditions corresponded to the needs of fiber flax for the cultivation of early and mid-ripening varieties. The resulting hybrid material was sown from 2013 in a selection nursery by pit planting on a specially prepared soil with a feeding area of 2.5 × 2.5 cm. In 2017–2019 hybrid lines were kept in nurseries of the second and third years of breeding. The hybrid lines’ potential was studied during the years which were different by meteorological conditions. Based on the results of this work, three tall hybrids were identified that had statistically significant differences with Tomskiy 16 standard and exceeded it by 5.8–7.6 cm in total height and 4.4–9.5 cm in the technical length of the stem. Nine hybrids showed high fiber content, exceeding the standard by 2.8-4.2%. These promising hybrid lines of fiber flax are recommended for use in the breeding process for high rates of maturity, productivity, fiber quality, adaptability to external environmental factors and resistance to lodging and diseases.