Novel bioengineering functional organoboron homo- and copolymer of maleic anhydride (MA) were synthe- sized by (1) amidolysis of anhydride-containing macromolecules [poly(MA-alt-methyl vinyl ether (MVE) as a bioengineering polymer] with 2-aminoethyldiphenylborinate (2-AEPB), (2) esterification with α-hydroxy-ω-methoxy-poly(ethylene oxide) (PEO) as a compatibilizer and (3) conjugation of organoboron PEO branches with folic acid as a targetting agent. Structure and composition of the synthesized oligomers were characterized by FTIR-ATR and 1H (13C) NMR spectroscopy. Antitumor activity of the organoboron functional (co)polymers were investigated by a combination of various physical and biochemical methods such as cytotoxicity, statistical, apoptotic and necrotic cell indexes, double staining and caspase-3 immunostaining, light and fluorescence inverted microscope analyses. It was found that cytotoxicity and apoptotic/necrotic effects of organoboron macromolecules significantly depend on the structure and composition of studied (co)polymers. Some synthesized (co)polymers at 400 μg.mL-1 concentration as a therapeutic drug exhibits minimal toxicity toward the normal cells, but influential for cancer cells.