Breast cancer is one of the most common diseases in the recent period, it is the second leading cause of death worldwide. More than 1.8 million new breast cancer cases are diagnosed every year worldwide. In Egypt, the estimated number of cancer cases According to the results of the national population-based cancer registration program increased in the period (20152020) from 19411 to 22682 and is expected to reach 46050 in 2050. In this paper, a system will be designed to detect breast cancer tumor. It consists of an array of 4*4 microstrip patch antenna operating at 8 GHz that transmit and receive signals from the breast. The scattering signals are collected by voltage network analyzer (VNA) that connected to pc to show the output image which illustrates if it is normal or malignant tissues.