The aim of this work was to synthesize methotrexate (MTX)-polyamidoamine (PAMAM) dendritic nanoconjugates and to study their effect on cell viability in uterine sarcoma cells. The amide-bonded PAMAM dendrimer-MTX conjugates were prepared by conjugation between the amine-terminated G5 dendrimer and the carboxylic groups of the MTX using a dicyclohexylcarbodiimide coupling reaction. The formation of conjugates was evaluated by ultraviolet (UV) and (1)H nuclear magnetic resonance ((1)H NMR) spectroscopy studies. The cell survival of MES-SA cells, a uterine sarcoma cell line, was evaluated in the presence of the dendrimer-MTX nanoconjugate, using appropriate controls. The UV and (1)H NMR study confirmed the formation of covalent bonds between the drug and the dendrimer. The cell viability study indicated that the nanoconjugates had significantly improved cell killing compared to the free MTX.