Summary Sunn pest (SP) is one of the most detrimental wheat bugs in Asia and Europe. Flour milled from SP damaged wheats (SPDW) exhibits weak dough characteristics and unsatisfactory baking quality due to its high protease content. l ‐ascorbic acid ( l ‐AA) and transglutaminase (TG) are the two different bread additives that lead to protein polymerisation via different mechanisms. This study aimed to compare the independent and combined effects of TG and l ‐AA additives in improving quality of bread made from SPDW. Compared to l ‐AA, TG is an additive that is much more effective for strengthening the dough. The positive effect of l ‐AA was more clearly found in flours with low‐level of SPDW (LLSPDW). Bread structure and properties of LLSPDW could be restored by addition of suitable‐levels of l ‐AA (75–100 mg/kg) and/or low‐level of TG (0.3%). High‐level of SPDW (HLSPDW) could be restored only by addition of suitable level of TG (≥1%). In bread‐making with HLSPDW flours, TG can be successfully used to maintain dough stability and bread attributes, however, the positive effect of l ‐AA remained at very limited levels and cannot compare with the contribution of TG. The results of this study can be utilised to improve the quality of breads made with SPDW flours.