The hair cells in both auditory and vestibular system display remarkable sensitivity to miniscule mechanical stimuli by employing a mechanism called negative stiffness. In this study, we developed and analyzed a conceptual mechanical model of the negative stiffness of the hair cells. The nonlinear stiffness including the region of negative stiffness was derived from gating springs hypothesis, which relates the transduction channel’s gating force to the stiffness change of the bundle, and was applied to a simple mass-spring-damper system. Sinusoidal stimuli of 0.1Hz~10Hz with magnitude of 1pN~1000pN, well within the dynamic range of vestibular organ, were applied to the system. The simulation was run on MATLAB and power transfers and sensitivities were obtained. The result showed compressive nonlinear sensitivity, which indicated the presence of selective amplification of smaller stimuli, as reported by the previous researches on the inner ear hair cells.