The present invention discloses a method and system for detecting the fastening state of a fastening structure which fixes structural elements. At least a first vibration sensor is mounted on a first structural element for collecting vibration data of the first structural element. At least a second vibration sensor is mounted on a second structural element or on the fastening structure for collecting vibration data of the second structural element or the fastening structure. The fastening state of the fastening structure is determined using the vibration data collected. The method and system enable detection of the fastening state of a fastening structure with low-power consumption and low cost.