The paper explores the design and analysis of a wideband microstrip patch antenna with a metallic patch and a 3 × 3 split ring resonator (SRR) array operating in the 0.1–5 THz frequency range. The antenna's structure incorporates different conductive materials such as gold, silver, and graphene as a metallic patch. The dimensions of the metallic patch and SRR are calculated to achieve wideband operation within the desired THz range. The SRR array enhances electromagnetic resonance, thereby improving bandwidth and radiation characteristics for medical imaging. The study discusses the equivalent circuit and design equations for the microstrip patch antenna and SRR unit cell. For designing and analyzing the proposed antenna, CST Microwave Studio 2019 software have been used. Performance parameters such as return loss, bandwidth, gain, efficiency, directivity, VSWR, and radiation pattern have been evaluated. The advantages and limitations of each conductive material are evaluated to determine their suitability for THz-based medical imaging applications. The goal is to maximize the antenna's bandwidth, gain, and image resolution for medical imaging purposes. The findings highlight the performance characteristics of gold, silver, and graphene as conductive materials for medical imaging applications, facilitating the development of high-resolution, non-invasive imaging systems with improved diagnostic capabilities.