To investigate the effects of cooked germinated highland barley pulp (CGHBP) on the dough properties and quality of barbecued pork buns (BPB), different amount of CGHBP [0%, 4%, 8%, and 12% (dry weight basis, DW%)] were added to the wheat flour. The thermo-mechanical characteristics, fermentation rheological properties, and water distribution of dough were analyzed using a Mixolab mixer, Rheo-F4 fermentation rheometer, and nuclear magnetic resonance imaging analyzer, respectively. The texture, pore structure, microstructure, and sensory quality of BPB were also measured. Results showed that with an increasing addition of up to 12% CGHBP, the C2 value decreased from 0.46 to 0.34, and the recovery value dropped from 2.12 to 0.91. Moreover, the maximum fermentation height decreased from 49.00 to 39.50 mm, representing a reduction of 19.4%. At 8% CGHBP addition, T'1 and the corresponding gas release reached maximum values, indicating the best thermal stability of starch gelatinization. The content of deeply bound water (A21) and weakly bound water (A22) significantly increased to 17.54% and 81.95%, respectively. As the addition of CGHBP increased from 0% to 12%, hardness showed no significant changes, exhibiting an increase of merely 7.51%. In contrast, elasticity decreased from 0.91 to 0.86, resilience from 0.40 to 0.36, and specific volume from 2.54 to 2.02 mL•g-1. At 12% CGHBP addition, pore uniformity in bun skin significantly deteriorated, with numerous pores appearing in the internal network. Sensory evaluation revealed gradual declines in shape, internal structure, and elasticity scores with a reduced specific volume, whereas flavor and aroma scores improved due to the pleasant flavor of CGHBP. Comprehensive analysis suggested 8% CGHBP as the optimal addition level for balancing dough properties and product quality. This study provides references for expanding the application of highland barley in Chinese steamed buns.