A method for detection of Staphylococcus Aureus using a RF Microelectromechanical systems based biological sensor is proposed in this manuscript. The sensor was structured in two ways, one is based on CPW (coplanar waveguide) and the other is based on DMTL (distributed micro-electromechanical systems based transmission line). The bacteria chosen for study are Staphylococcus aureus which were modelled as a spherical-shell structure derived from their electrical properties. Initially the coplanar waveguide model was used. The scattering parameters were examined and found to deviate with the increase in the amount of bacterial cells placed on the waveguide. Furthermore, the DMTL was designed by introducing equally spaced nickel bridges over CPW. Improvement in the quality factor of resonant peaks was observed through the study of its reflection coefficients and therefore helps associate the amount of bacterial cells to the change in resonant frequency. © 2018 IEEE.