We investigated the influence of N-stearoylethanolamine (NSE) on tumor growth and metastasis of the lung Lewis carcinoma in mice. The effect of NSE on lipid composition of lung tissue under tumorogenesis was also studied. We demonstrated that NSE inhibited the tumor growth and decreased the volume and quantity of metastases being administered from the fourth day after injection of tumor cells to the last day of experiment and being administrated from the 21th day after injection of tumor cells to the last day of the experiment. The analysis of the lipid composition of the lung tissue showed the decrease of total phospholipid levels and change of the phospholipid spectra under tumor growth. The decreasing of the concentration of phosphatidylcholine, sphyngomyeline, phosphatidylserine and lysophosphatidylcholine in the lung tissue of tumor-bearding mice in comparison with lung of intact animals was observed. It was found that administration of NSE increased the level of lysophosphatidylcholine and decreased the concentration of phosphatidylinositol in investigated tissues. The content of sphingosine was increased in lung tissue of mice fed by NSE in comparison with tumor-bearing mice. The carcinoma development was associated by the significant decreasing of cholesterol level and by the increasing of unsaturated fatty acids in membrane phospholipids. The amount of the tiobarbituric acid (TBA) reactive substances in tumor-bearing mice was elevated. The administration of NSE inhibited the accumulation of TBA reacting compounds.