Studies have reported different changes in the fatty acid composition of red blood cell (RBC) total lipids in patients with various types of cancer. It has been indicated that n-3/n-6 ratio plays a key role in the general consequence of skin photocarcinogenesis. However, to our knowledge there was no study examining the unsaturated fatty acid profile in basal cell carcinoma (BCC) patients. So, we explore the fatty acid composition of RBCs in newly diagnosed BCC patients in a hospital-based case-control study. This study has been conducted on new case BCC patients in Razi Hospital, Tehran, Iran. Fatty acid concentration in erythrocyte membranes defined as relative values after extraction, purification and preparation, by gas chromatography.Analysis revealed that heptadecenoic acid (p = 0.010) and oleic acid (p < 0.001) was significantly higher in BCC patients in comparison with control group. Among polyunsaturated fatty acids (PUFAs), linoleic acid (LA), and arachidonic acid (AA) were significantly higher in BCC patients (p < 0.001). It has been indicated that n-3 was significantly lower (p = 0.040) and n-6 was significantly higher (p = 0.002) in BCC patients. In addition, total PUFA (p < 0.001) and n-6 PUFAs/n-3 PUFAs (p = 0.002) were significantly higher in BCC patients compared to the control group. Here we indicated that new case BCC patient had significantly higher n-6 PUFA and lower n-3 along with other differences in unsaturated fatty acid in comparison with healthy subjects. Our study provides evidence that lipids are important in BCC development.