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Flax is an important cash crop globally with a variety of commercial uses. It has been widely used for fiber, oil, nutrition, feed and in composite materials. Growth regulatory factor (GRF) is a transcription factor family unique to plants, and is involved in regulating many processes of growth and development. Bioinformatics analysis of the GRF family in flax predicted 17 <i>LuGRF</i> genes, which all contained the characteristic QLQ and WRC domains. Equally, 15 of 17 <i>LuGRFs</i> (88%) are predicted to be regulated by lus-miR396 miRNA. Phylogenetic analysis of GRFs from flax and several other well-characterized species defined five clades; <i>LuGRF</i> genes were found in four clades. Most <i>LuGRF</i> gene promoters contained cis-regulatory elements known to be responsive to hormones and stress. The chromosomal locations and collinearity of <i>LuGRF</i> genes were also analyzed. The three-dimensional structure of <i>LuGRF</i> proteins was predicted using homology modeling. The transcript expression data indicated that most <i>LuGRF</i> family members were highly expressed in flax fruit and embryos, whereas <i>LuGRF3</i>, <i>LuGRF12</i> and <i>LuGRF16</i> were enriched in response to salt stress. Real-time quantitative fluorescent PCR (qRT-PCR) showed that both <i>LuGRF1</i> and <i>LuGRF11</i> were up-regulated under ABA and MeJA stimuli, indicating that these genes were involved in defense. <i>LuGRF1</i> was demonstrated to be localized to the nucleus as expected for a transcription factor. These results provide a basis for further exploration of the molecular mechanism of <i>LuGRF</i> gene function and obtaining improved flax breeding lines.