A sensor system includes a sensor that is provided in a structure and detects an acceleration, a storage unit that stores installation information indicating a relationship between a direction of a gravitational acceleration and a direction of a detection axis of the sensor, and a drop determination unit that determines whether or not the sensor is dropped based on a representative value of accelerations in the direction of the detection axis detected by the sensor and a gravitational acceleration value in the direction of the detection axis specified based on the installation information.