Tumor growth is a process associated with an enhanced rate of membrane phospholipids de novo turnover and assembly. Erythrocytes are the initial objectives for circulating drugs. In addition, erythrocyte membrane structural compounds are similar to those in many cell types of the organism. In malignant cells, the ultra structural architecture of the cell membrane is altered, partially as a result of changes in the quantities of membrane components present. We aimed to study the effect of flaxseed and corn oils on erythrocyte membrane components in Ehrlich ascites carcinoma (EAC) and solid carcinoma in mice. Sixty four healthy albino female mice weighting 20- 25 g were divided into 8 groups; corn oil, flaxseed oil, EAC, solid tumor, EAC treated with corn oil, EAC treated with flaxseed oil, solid tumor treated with corn oil and solid tumor treated with flaxseed oil. Results showed that liver functions, α-fetoprotein, erythrocyte membrane lipid profile and phospholipid fractions were improved in EAC and solid tumor groups treated with corn and flaxseed oils compared to untreated groups, which may be due to improvement of membrane components especially phospholipids, these results were confirmed by histopathological examination. We concluded that polyunsaturated fatty acids (PUFA) had a good effect in the treatment of EAC and solid tumor.