Five novel dinuclear platinum(II) complexes with a new chiral ligand, 3‐(2‐amino‐cyclohexylamino)‐propionic acid (HP), were designed, prepared and spectrally characterized. The in vitro cytotoxicities of these compounds were evaluated against the HepG‐2, MCF‐7, A549, and HCT‐116 cell lines. The results indicated that all compounds showed cytotoxicity towards the HepG‐2 cell line. Particularly, complex X5, which has SO as a bridge, exhibited better cytotoxicity than carboplatin or oxaliplatin against all selected cell lines. Moreover, double dyeing flow cytometric resection indicated that the target compounds inhibited tumor cell growth by inducing apoptosis.