Based on the latest research results about ice slurry on HVAC，this paper analyzes the annual cost of secondary piping network of ice slurry & ice storage central cooling system. Fitting the function of secondary pipe network annual cost per unit length and analyzing the applicability of ice slurry central cooling system. The results show that adopting ice slurry central cooling system in Guangzhou will effectively reduce the secondary piping network investment and the advantage of ice slurry central cooling system will increase with the extension of cooling period，cooling load and the length of secondary piping network.