This article explores the potential cytotoxic activity of bile-acid cisplatin derivatives like bisursodeoxycholate(ethylenediamine)platinum(II), PtU2, when conjugated with gold nanoparticles, being a promising alternative to cisplatin in the treatment of cancer due to their lower toxicity. For our purpose we analyzed the intracellular delivery ability of these compounds after conjugation with 20-nm gold nanoparticles (PtU2-AuNPs) in the MG63 (osteosarcoma) cell line. Same platinum uptake after incubation with PtU2 and PtU2-AuNPs-derivatives is associated with a higher cytotoxic activity in case of the platinum-gold nanoparticle conjugate, the overall IC50 of PtU2 being reduced more than 10 fold for these new conjugates. When conjugated with gold nanoparticles, this bile-acid derivative is more efficient than the platinum compound alone in terms of their cytotoxic activity.