The proposed work aims to monitor tumors in the human head and distinguish them from a normal brain. An ultra-wideband (UWB) microstrip-fed Vivaldi antenna with a gain of 8.8 dB is proposed to achieve this. A human head model is designed using CST, incorporating different tissue layers with appropriate properties. Results were obtained and verified for both tumour-free and tumour-present conditions using the proposed antenna. The reflection coefficient showed a significant difference, ranging from –24 dB to –37 dB, effectively differentiating a normal head from one with a tumor. The tumor-inside head model exhibited a higher specific absorption rate (SAR) compared to normal head tissue. Other key performance characteristics of the suggested antenna, such as reflection S11, gain, directivity, bandwidth, and E-field strength, were also examined for both normal and tumor-induced head tissue models. Ultimately, the suggested antenna is strongly competent for identifying tumors in the human head.