The aim of the present study was to compare the effects of ground grape pomace (GGP) and olive cake (OC) addition on the sensory properties, content of phenolic compounds and dietary fiber, antioxidant and antimicrobial activity of wheat bread. Dough rheological characteristics were analyzed with farinograph analysis. Bread volume, firmness and color were measured, a sensory analysis of bread was made. The content of total phenolic compounds in GGP and OC, dough and bread were determined with the Folin–Ciocalteu method. Antioxidant activity were determined with the DPPH• and FRAP methods and content of individual phenolic compounds with the LC-MS method. The enzymatic-gravimetric method was used to determine the content of soluble, insoluble and total dietary fibers. Antimicrobial activity was analyzed with and without the inoculation of chosen mold strains. The addition of GGP affected the rheological characteristics of dough; the addition of variety 'Merlot' has extended the dough development time and stability, as well as reduced the degree of softening. The variety 'Zelen' had a reverse effect. The volume was lower in all breads with GGP and OC addition in comparison to the control bread, the firmness was greater and the bread color was changed. The crust surface and crumb pores were inhomogeneous and the pores were bigger. The springiness and toughness of the crust was lower, crumbliness, adhesivity and the sand feeling during chewing were increased, as well as the sour and sweet odour. The addition of GGP caused the sour taste, aftertaste and off-flavor, while the addition of OC enhanced the bitter taste. The content of the total phenolic compounds was getting higher with the addition of GGP and OC, so did the antioxidant activity. The LC-MS analysis has shown the instability of some phenolic compounds, despite the presence in GGP and OC, these were not present in the bread. The content of total dietary fiber got higher with the GGP addition of both varieties, while OC had no impact on it. The analysis of antimicrobial activity without inoculation has shown inhibitory activity of GGP of both varieties. The mold growth was more intense on the bread with OC as on the control bread. The analysis with inoculation of individual mold strains has shown no inhibitory activity.