Institute of Chemistry of Macromolecular Chemistry NAS of Ukraine, 48, Kharkivske shose, Kyiv, 02160, Ukraine Developed polymer composite material with Cefazolin based on polyurethane with isocyanurate fragments (PU), synthesized on the basis of polyoxypropylene glycol (POPG 1000), TDI (2,4;2,6-toluene diisocyanate) and 2,4,6-triisocyanate(trishexamethylene) isocyanate (ICC, Tolonate ™ HDT-LV, MM 1200) at a ratio of NCO: OH = 1: 1 in the medium N,N’-dimethylacetamide (DMAA) and Cefazolin (CFZ). CFZ is immobilized on isocyanurate-containing polyurethane by introducing a solution of CFZ with DMA into the reaction the amount of 5 wt. %. The synthesized polymeric material (PU-CFZ) represents a transparent film of yellow color with physical and mechanical characteristics: σ = 0,15 MPa; ε = 63.40%. According to IR spectroscopy, Cefazolin is immobilized on the polymer matrix by physically due to hydrogen interactions. The influence of biological medium 199 (BM 199) on the structure and properties of PU-CFZ during incubation for 1, 3 and 6 months was studied. It was found that after incubation in BM 199, the structure of PU-CFZ changes as a result of the interaction of enzyme molecules that are part of BM 199 with urethane and amide groups of PU. According to the results of physical and mechanical studies, after incubation in BM 199 for 6 months, PU-CFZ samples are characterized by tensile strength of 0.36 MPa and elongation at break of 98%, ie retain sufficient performance for use in biological objects for up to 6 months. Composite materials with Cefazolin are able to prolong the release of the drug for 28 days in an amount of about 30%, which is sufficient to provide a local therapeutic effect. According to the results of the cytotoxicity study of the developed material by in vitro tissue culture, it was found that the composite material based on isocyanurate-containing polyurethane with Cefazolin is biocompatible.