PROBLEM TO BE SOLVED: To provide a system which can calculate an operation state suitable for the management of a work machine by using not only operation information acquired during the operation of the work machine but also work supplementary information acquired by an information terminal.SOLUTION: A work management system comprises a data collection device 2 for collecting operation information, during the operation of a work machine, acquired by the work machine, an information terminal 4 that can input work supplementary information, which is supplementary information on work, and a server 6 that can acquire operation information and the work supplementary information, in which the server calculates an operation state based on the work supplementary information and operation information.
