In this paper, Microstrip-Fed Vivaldi Antenna for the Medical Applications have been presented. During the course of time, the antenna was made to resonant in between 400 MHz-3 GHz with possibility of achieving in trends of Medical Microwave Imaging. As a result of which the requirements of working with the Lower Frequency are achieved where the Antenna witnessed Gain of around 11.77 dBi at an Highest Level of Frequency. With regard to this Equivalent Circuit Modelling of it is done, which satisfies the main motives of working in MICS Band as specified by Medical Device Radiocommunications Service as set aside by the US FCC for the needs of diagnostics and therapeutic medical implants. All major Simulation's has been carried by CST-MWS and there is a use of Rogers RT 5870 Substrate.