This paper describes the synthesis of the new β-ketoimine 4-(3-triethoxysilylpropylimino)-3-ethyl-pentan-2-one, and studies its structure, solubility in water and complexation properties in terms of the possibility of its further application for water and wastewater treatment, especially for removing metal ions from aqueous solutions. The synthesis procedure consisted of the addition of 3-ethyl-pentane-2,4-dione to 3-aminopropyltriethoxysilane and subsequent elimination of the water molecules. The structure of the resulting compound was confirmed by Nuclear Magnetic Resonance and Fourier Transform Infrared Spectroscopy-Attenuated Total Reflectance. The affinity of the resulting compound for metal ions binding from aqueous solutions was studied using spectrophotometric methods. Moreover, the stability constants of created in this process complexes of a new β-ketoimine with selected metal ions (Ag+, Au3+, Cd2+, Co2+, Cr6+, Cu2+, Fe3+, Mg2+, Ni2+, Pd2+, Pt2+, Zn2+) was determined and it was found that the stability of created complexes of L:M with molar ratios equal 1:1 are changing as follows: Pd2+ > Cr6+ > Pt2+ > Ni2+ > Cd2+ > Cu2+ > Ag+ > Fe3+ > Zn2+ > Co 2+> Au3+ > Mg2+.