Breast cancer is one of the most malignant tumors in women across the globe. Diagnosis of breast cancer at early stages is essential to improve treatment outcomes and decrease mortality rates. There is a pressing need for new non-invasive biomarkers to improve early diagnosis of breast cancer. This study aims to assess plasma miR-27a for the early diagnosis of breast cancer. miR-27a was evaluated in a total of 95 blood samples, 40 newly diagnosed cancer patients, 20 patients with benign breast lesions, 20 females with positive family history for breast cancer and 15 apparently healthy controls, using quantitative real time polymerase chain reaction. Our results exhibited significantly higher expression level of plasma miR-27a in breast cancer patients (median= 8.3 and 19 fold change for early and late stages respectively) compared to controls, high risk group and benign group with (P <0.001) for each. Plasma miR-27a was significantly higher in late breast cancer (median=19 fold change) compared to early breast cancer (median= 8.3) with (P <0.001). There was no statistically significant difference of plasmamiR-27a levels in benign group (median=1.8 fold change) compared to both control group and high risk group. There was no statistically significant difference of plasma miR-27a levels in high risk group (median= 1.2 fold change) compared to control group (median= 1 fold change). We performed Receiver Operating Characteristic (ROC) analysis for discriminating malignant from non-malignant cases. Plasma miR-27a yielded an area under the curve (AUC) of 0.983 with sensitivity 97.5%, specificity 91% and accuracy 94%.We concluded that miR-27a expression level represents sensitive and specific non-invasive molecular biomarkers for diagnosis of breast cancer.