A modified Model-Free Sliding Mode Controller (MF-SMC) scheme, which based on the Biogeography-Based Optimization (BBO) algorithm is suggested, to regulate the heart rate since it is difficult to derive a suitable model for the control algorithm, therefore the traditional control algorithm cannot perform efficiently. Also, a smoothing boundary layer is used to eliminate the chattering in the MF-SMC control signal. Results of simulation effort show that overshoot less and fast performance is achieved with stable convergence for the tracking regardless of the heart rate model to be controlled.