The obtained new product of reaction of the complex cis-diammin(cyclobutane 1,1 dicarboxylato)platinum(II) with arabinogalactan was characterized by XRD, IR-spectroscopy, UF-spectrophotometry and thermogravimetry. The composition and structure of this product was studied. It has been shown that cis-diammin(cyclobutane 1,1 dicarboxylato)platinum(II) associated with arabinogalactan through communications

 -C-C-O- groups by hydrogen of the original complex.