Supplementation of food products with mushroom powder increases their health-promoting value, but at the same time affects technological quality, which often play a key role for consumers. The aim of the research was to determine the effect of adding freeze-dried white and brown button mushrooms (2.5% and 5%) to wheat bread on its health-promoting properties such as antioxidant activity (DPPH, FRAP), total polyphenols and vitamin D2 content and as well as the technological quality as colour and texture. The breads were supplemented with mushroom lyophilisates, which were exposed to UVB radiation in order to increase their vitamin D2 content. The content of total polyphenols and antioxidant properties were determined spectrophotometrically, and the content of vitamin D2 by ultra-high performance liquid chromatography coupled to triple quadrupole spectrometer (UHPLC/MS/MS analysis). Colour parameters were determined in the CIE-Lab system and texture profile analysis (TPA) and sensory evaluation of the baked products were performed. The addition of dried mushrooms significantly increased the content of bioactive compounds (total polyphenols, vitamin D2) and the antioxidant properties of bread. A small addition of mushrooms caused a significant change in the basic technological quality of breads (colour parameters, specific volume, hardness, cohesiveness, springiness). At the same time, supplementation with mushroom lyophilisates has a positive effect on most analysed attributes in the nine-point hedonic scale. Based on the conducted research, it can be concluded that mushroom lyophilisates can be a valuable raw material for the fortification of bread, which is a good matrix and carrier of substances with documented biological activities. Keywords: functional breads; mushroom powder; vitamin D2; ergocalciferol; polyphenols; antioxidants; colour; texture