Angiogenesis-dependence of tumor’s growth is known for more than 30 years. Studies on the influence of heparin and its derivatives (as low molecular weight heparins /LMWH/) on tumor angiogenesis were done and given different results. As LMWH are widely used in deep venous thrombosis /DVT/ prophylaxis in patients with neoplastic disease, we tried to check influence of enoxaparin and nadroparin on tumor angiogenesis and tumor growth in mice. Experiments were done in inbred Balb/c mice whom L-1 sarcoma cells were grafted subcutaneously or intradermally. Nadroparin highly significantly increased, and enoxaparin significantly decreased neovascular reaction induced in syngeneic mice skin on the 3-rd day after cells grafting. Cytokines concentration (VEGF and bFGF) in 5-th days lesions behaved similarly as neovascular reaction (enoxaparin decreased VEGF and bFGF content in comparison to the control, nadroparin increased bFGF concentration). Fourteen days after sarcoma cells grafting VEGF concentration was similar in all groups, and the only one difference from the control it was higher bFGF content of tumors collected from nadroparin – treated mice. Histological examination of the lesions didn’t revealed serious changes between control and experimental groups of animals.