In this study, functional buns with the addition of green tea extract (GTE) were prepared to evaluate the in-vitro digestibility, glycemic response, physicochemical, thermal, and antioxidant properties. Green tea extract was obtained using an ultrasound-assisted extraction method. The extracted GTE was incorporated in whole wheat flour at different concentrations of 1, 3, and 5% to make green tea-fortified buns (GTEB). ATR-FTIR displayed a decrease in transmittance with an increase in concentration of GTE. Results revealed that the texture profile of functional buns varies non-significantly (P ≤ 0.5) with the addition of GTE. Color values for crumb and crust showed significant difference (P ≤ 0.5) with the addition of GTE. DPPH scavenging activity, reducing power (Rp), total phenolic content (TPC), and lipid peroxidation inhibition (ILP) were accessed which revealed that antioxidant activity increased significantly (P ≤ 0.5) as the concentration of GTE increased. The in-vitro digestibility assay of buns fortified with green tea extract displayed a slow rate of digestion of functional buns which suggests it inhibits starch digestion. This method is anticipated to develop low glycemic bakery products for the expanding diabetic population of the world. Additionally, the buns developed from GTE can be utilized to produce functional foods with improved nutraceutical and antioxidant potential. The sensorial analysis of the functional buns indicated that the addition of the GTE did not impact the acceptability of the buns, as perceived by consumers.