Nanocomposites incorporating titanium dioxide (TiO) have a significant potential for various industrial and medical applications. These nanocomposites exhibit selectivity as antimicrobial and anticancer agents. Antimicrobial activity is crucial for medical uses, including applications in food processing, packaging, and surgical instruments. Additionally, these nanocomposites exhibit selectivity as anticancer agents. A stable nanocomposite as a new anticancer and antibacterial chemical was prepared by coupling titanium dioxide nanoparticles with a polyurethane foam matrix through the thiourea group. The titanium dioxide/thiopolyurethane nanocomposite (TPU/TiO) was synthesized from low-cost Ilmenite ore and commercial polyurethane foam. EDX analysis was used to determine the elemental composition of the titanium dioxide (TiO) matrix. TiONPs were synthesized and were characterized using TEM, XRD, IR, and UV-Vis spectra. TiONPs and TPU foam formed a novel composite. The MTT assay assessed Cisplatin and HepG-2 and MCF-7 cytotoxicity in vitro. Its IC values for HepG-2 and MCF-7 were 122.99 ± 4.07 and 201.86 ± 6.82 µg/mL, respectively. The TPU/TiO exhibits concentration-dependent cytotoxicity against MCF-7 and HepG-2 cells in vitro. The selective index was measured against both cell lines; it showed its safety against healthy cells. Agar well-diffusion exhibited good inhibition zones against Escherichia coli (12 mm), Bacillus cereus (10 mm), and Aspergillus niger (19 mm). TEM of TPU/TiO-treated bacteria showed ultrastructure changes, including plasma membrane detachment from the cell wall, which caused lysis and bacterial death. TPU/TiO can treat cancer and inhibit microbes in dentures and other items. Also, TPU/TiO inhibits E. coli, B. cereus, and A. niger microbial strains.