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In cereal crops such as wheat, seed dormancy is closely associated with the occurrence of preharvest sprouting (PHS), germination of the grain prior to harvest under moist conditions. While higher level of seed dormancy results in a delay in germination, low level of seed dormancy causes preharvest sprouting which negatively affects yield and end use quality of wheat grains. Therefore, it is necessary for wheat grains to have certain level of dormancy to prevent preharvest sprouting. Abscisic acid (ABA) is one of the plant hormones that predominantly regulates seed dormancy and germination, and molecular elements involved in its metabolic and signalling pathways play crucial roles in this regard. The ABA catabolic gene ABA 8′-hydroxylase 1 (ABA8′OH1) has been known as a key regulator of the amount of ABA in the seeds of several plant species while the transcription factor abscisic acid insensitive 5 (ABI5) plays pivotal role to determine ABA responsiveness of the seed, which in turn influences the degree of dormancy. To better understand the roles of ABA8′OH1 and ABI5 in wheat seed dormancy and germination, the present study performed molecular characterization and expression analysis of the genes in different wheat genotypes that showed a range of dormancy phenotypes.