Characterization of high-molecular-weight (HMW) glutenins is an important criterion for identifying genotypes with good bread-making quality. In synthetic hexaploids (SHs), the D-genome encodes several allelic variants of HMW glutenins that require proper identification prior to their utilization for bread wheat (BW) improvement. In this study, SHs with promising agronomic features were characterized for HMW glutenin composition. Seven different allelic variants were observed at the Glu-Dt1 locus, three of which (1Dx1.5+1Dy10, 1Dx1.5+1Dy12.2 and 1Dx2.1+1Dy10) have not been previously reported in existing BW germplasm. The results also showed a variety of D-genome-encoded subunits along with superior glutenin alleles in the B-genome (1Bx7+1By8, 1Bx6+1By8 and 1Bx13+1By16). About 63% of these SHs encoded favourable allelic variants of HMW glutenins, which make them a good choice for improvement in wheat bread making. Glu-Dt1 encoded favourable allelic variants (1Dx5+1Dy10 and 1Dx1.5+1Dy10) that are frequently observed in SHs can be easily incorporated into BW through recombination breeding.