Abstract: A monitoring system according to one aspect of the present disclosure includes: a sensor to measure physical quantities at one or a plurality of measurement points of a structural body; processing circuitry configured to acquire measured values from the measurer; a memory to store the measured values acquired from the measurer; and a data storage that, when one or some of the measured values stored in the memory satisfy a predetermined trigger condition, and as a result, it is determined that the structural body has received impact, records a group of data of the measured values which are within a certain time range and include the measured value based on which it is determined that the trigger condition is satisfied.