A construction management system includes: an object detecting unit mounted on a work machine and configured to detect an object in a construction site and output information on the object; a shape detecting unit configured to output shape information indicating a three-dimensional shape of the object by using the information on the object detected by the object detecting unit; an information attaching unit configured to attach, to the shape information, time information indicating a time when the object is detected; and a management device configured to generate current state information on the construction site on the basis of the shape information to which a latest piece of the time information is attached.