IR, TGA, UV/Vis, and ¹HNMR techniques together with powder X-ray diffraction, elemental (CHN) and mass spectra analysis, molar conductance, and magnetic susceptibility studies were utilized to synthesize and report novel imine-complexes of Pr(III); Nd(III) and Sm(III) cations. The conductivity measurements demonstrate that none of the complexes are electrolytes. Data of magnetic susceptibility support the paramagnetism of all lanthanide (III) complexes. Depending on various analyses, trivalent cations favor a 1:1 lanthanide: ligand. According to biological investigations, every complex demonstrated effective antimicrobial efficacy against a wide variety of bacterial and fungal strains. Additionally, we noticed that the Ln (III) complexes' antimicrobial potency was ordered as follows: NdA > PrA > SmA > H₂A. It was determined that the Nd(III) combination had the maximum inhibition zone (22 mm) and was the most efficient against Gram-negative bacteria. The antimicrobial effectiveness against fungus (A. Flavus) goes as follows: PrA > NdA > SmA > H₂A. The equilibrium geometry of the imine ligand and its complexes at the B3LYP level of theory, where (C, H, O, N, and Cl) atoms at 6-311G++(d, p) and Nd, Pr, and Sm at SDD, was clarified using density functional theory (DFT) calculations utilizing the Gaussian 09 program. Lastly, docking experiments have shown. Ultimately, this research aspires to contribute to developing novel metal-based drugs with enhanced therapeutic propereties.