A novel compact tapered microstrip slot antenna has been developed for microwave breast imaging. The antenna is designed assuming that it will be embedded in breast tissues rather than air. By using a microstrip tapered slot with a fork-shaped feeding structure, the designed antenna has achieved a good matching performance at 2 to 8 GHz. The total size of the antenna is only 0.13λ × 0.13λ at the lowest operation frequency 2 GHz. The designed antenna also shows good near-field radiation characteristics. Time domain response of a Gaussian pulse transmission between two identical antennas presents a very low distortion of the pulse shape (pulse broadening). The designed antenna is a potential candidate element of a half-spherical antenna array for radar-based breast cancer detection.