<p>The increasing resistance of bacteria and cancer to present treatments is a clinical and laboratory concern. In this study, a novel Schiff base ligand (HL) was synthesized in this work through a solvent-free method, involving the reaction of 2,4-diamino-6-phenyl-1,3,5-triazine with 2-hydroxy-1-naphthaldehyde under mild and eco-friendly conditions. The Ni(II) and Zn(II) complexes were then synthesized and confirmed by different spectroscopic and analytical methods. The results suggest that both complexes have an octahedral geometry, in good agreement with the computational findings. The binding mood of these compounds with CT-DNA was examined using cyclic voltammetry and UV-vis spectroscopy, which revealed a partial intercalation mode. The findings demonstrated strong DNA-binding affinity with binding constants (K_b) of 2.51 × 10⁵ and 5.69 Χ 10⁵ M^− 1 for NiL₂ and ZnL₂ complexes, respectively. The calculated free energy (ΔG) values confirmed that these interactions with DNA are strong and spontaneous. Additionally, the compounds’ anticancer efficacy was tested against HepG-2 liver cancer cells. IC₅₀ values for HL, NiL₂, and ZnL₂ were calculated and determined to be (94.10, 51.08, 43.94) µg/mL. This shows that these complexes can preferentially treat liver cancer. The tested microorganisms demonstrated better response to metal complexes compared to the Schiff base ligand. Finally, molecular docking studies were performed to determine the binding interactions and affinities of the prepared compounds with the active site of the receptors associated with liver cancer (5A19) and <i>A. flavus</i> (8HBS). The study revealed adding metal ions considerably raised molecular affinities, and the binding potency sequence was ZnL₂&gt; NiL₂ &gt; HL ligand. According to experimental and theoretical evidence, the novel prepared ligand and its metal complexes have great promise as multifunctional bioactive agents, enabling additional pharmacological and biological applications.</p>