This is a prospective laboratory-based study, conducted at Rahma medical centre, Khartoum, during the period from March to July 2018. The study aims to evaluate the expression of E-cadherin and Vimentin as prognostic markers for epithelial- mesenchymal transition and tumour aggressiveness in breast cancer. Fifty six paraffin blocks are collected from archive for women previously diagnosed as breast cancer. Tissue microarrays are prepared, and then stained by immunohistochemistry method. The data obtained was analyzed using SPSS program version 22.0. The age of patients ranged between 30 to 80 years with a mean of 51.1. The histopathological diagnosis reveals that the invasive ductal carcinoma is 71.4%, while medullary carcinoma and mucinous carcinoma are 25% and 3.6% respectively. The result of histological grade shows, grade I is 10.7%, grade II is 35.7% and 53.6% for grade III. The study shows E-cadherin expression is negative in 12.5%, weakly expressed in 32.1%, moderately expressed in 48.2% and strongly expressed in 7.1%. The study reveals a significant correlation between E- cadherin expression with ages and histological grades (p.value= 0.028 – 0.027) respectively. Vimentin expression is negative in 1.8%, weakly expressed in 51.8%, moderately expressed in 46.4%. This results show a significant correlation between Vimentin expression with ages and histological types (p.value= 0.016 – 0.004) respectively. The study reveals an inverse correlation between E-cadherin and Vimentin (r = -0.389) with a significant correlation (p.value= 0.002). The study concludes that, decreased expression of E-cadherin and increased expression of Vimentin are associated with epithelial- mesenchymal transition and breast carcinoma aggressiveness.