The obtained product of reaction of the complex cis-dichlorodiaminplatinum(II) with matrix carrior arabinogalactan was characterized by XRD, IR-spectroscopy and thermogravimetry. The composition and structure of this product was installed. It has been shown that cis-dichlorodiaminplatinum(II) associated with arabinogalactan through communications –C-O-C- amino hydrogen of the original complex. The preliminary study of a synthesized product on the biological activity showed that the product inhibits tumor growth and it does not have toxic effects on the body. This product is more soluble and exibits a greater activity as compared to cis-dichlorodiaminplatinum(II).