A steam-using facility simulation system for efficiently searching for an approach for improving a steam-using facility that is effective in overall improvement of a steam-using facility and a method for searching for an approach for improving a steam-using facility are provided. The system includes storage means configured to store steam usage state information of the steam-using facility; input means to which facility improving approach information of the steam-using facility is input; simulating means configured to compute predicted steam usage state information of the steam-using facility after implementation of the improving approach based on the steam usage state information of the steam-using facility stored in the storage means and the facility improving approach information input to the input means; and output means configured to output the predicted steam usage state information of the steam-using facility computed by the simulating means.