A bio-inspired structural health monitoring (SHM) system based on multi-scale Sample Entropy (SampEn) is proposed in this paper. Recently, studies on entropy have shown that the healthy state of human can be evaluated by analyzing the measured electrocardiogram. As similar circumstance is also faced in the field of structural health monitoring, where the vibration signal of the structure can be measured by deployed sensors, a multi-disciplinary research is inspired and conducted. Numerical simulation has verified that the damage location and condition can be detected by the proposed SHM algorithm by processing the ambient vibration signal.