at least one sensor attached to or installed around the worker to monitor the state of the worker and to output state information indicating the state of each of the worker or a plurality of workers in association with time information and identification information of the worker;

a first database storing the state information indicating the state of each of the worker or the plurality of workers in association with the time information and identification information of the worker, the state information including at least any one of positional information of the worker, motion information indicating whether a hand of the worker is moving or not, and information indicating an operating state of an equipment around the worker;

a processing unit acquiring second state information by executing averaging and/or majority decision processing for one or a plurality of pieces of first state information in the pieces of the state information, and storing the first state information indicating a plurality of pieces of position information in a short period and the second state information in the first database;

an estimation unit estimating the work content executed by the worker on the basis of a least two pieces of state information associated with same time in the state information stored in the first database, the work content including indicating whether the worker is doing work or is not doing work;

a specification unit specifying work time spent for each estimated work content indicating whether the worker is doing work or is not doing work on the basis of the state information stored in the first database and the time information associated with the state information;

an analysis unit analyzing the work content on the basis of the estimated work content and the specified work time; and

a display to graphically display an output of the analysis unit.