This study is related with the energy saving of factory buildings, and automotive factory building are targeted for the study. Thus, energy saving strategies of factory buildings have been derived, being focused on automotive factory building, and then the energy saving factors that can be applied to the target factory buildings, have been selected. And then the energy consumption of heating, cooling and lighting, and total energy consumption have been calculated. Through this, the optimal combination by energy, has been derived and each integrated saving model has been proposed.