To provide a vibration detector recording the time when a vibration was detected during the stoppage of an automobile.

A vibration detecting circuit 10 detects the vibration of an automobile. A memory 20 stores a threshold value for comparing the levels of vibrations detected by the vibration detecting circuit 10 from each other and the times when the vibrations were detected. A clock 40 is installed to record the time when the vibration detecting circuit 10 detects a vibration. A control part 70 compares the level of the vibration detected by the vibration detecting circuit 10 with the threshold value stored in the memory 20 and, when the level of the vibration detected is larger than the threshold value, receives the time when the vibration was detected from the clock 40 and stores the time into the memory 20.