THIS DATASET WILL BE AVAILABLE AS SOON AS THE RELATED PAPER IS ACCEPTED FOR PUBLICATION BY THE JOURNAL. This dataset includes comprehensive analytical and experimental data on xylooligosaccharides (XOS) obtained from wheat straw. It covers their structural characterization (HPLC-RID, FTIR), in vitro digestibility, antioxidant activity (DPPH assay), cytotoxicity (Alamar Blue assay), prebiotic effects (probiotic bacteria growth assays), and immunomodulatory potential (study of pro-inflammatory cytokines expression by RT-PCR and NF-κB pathway assays). The data support the use of wheat straw-derived XOS as sustainable, health-promoting nutraceuticals and functional food ingredients.