A b s t r a c tFlax is the only industrial crop cultivated in Belarus for fiber on the area over 50 thousand ha. An environmental adaptation is of special interest for innovative flax varieties. We focused on selection of genetic sources of adaptability and stability and the search for environmentally adapted genotypes among the extensive flax hybrids. For this, we have studied a response of the parent forms and 36 hybrid populations of fiber flax to abiotic factors and estimated the influence of environment on economically important traits. The field trials (Orshanskii Region, Belarus, 2012 to 2014) were carried out under weather conditions which varied in precipitations (16.7-27.1 mm) and daily air temperature (12.4-16.4 С). Plant height, stem technical length, weight, and fiber content were studied in 10 parental varieties different in geographic origin (i.e. derived from Belarus, Russia, France, Ukraine, Lithuania), and also in their combinations. Morphological and biological screening identified 11 early ripening combinations, 15 forms with tall stem, 10 forms with a significant technical stem length, 4 ones with high stem weight, and 3 ones with high fibre content. Keywords: flax, varieties, hybrids, environmental adaptability, stability, productivity Nowadays, the fiber flax selection is focused on improving resistance to biotic and abiotic factors while preserving the high productivity and quality of the feedstock. The main method in generating the parent material is still the intravariety hybridization which allows combining important traits of parents [1].In the literature, there is sufficient information on the environmental study of varieties and hybrids of many crops, such as grains [2][3][4][5][6][7], corn [8,9) [19]. At the same time, there are extremely little papers dedicated to the environmental assessment of samples,