Energy conservation test in central heating/cooling system using surfactant drag reduction was performed using the building of the Sapporo City Hall. It equips a pump with 37kW rated output for some 32tons of circulating water. LSP-01A was used as a surfactant and its concentration set at 0.4-0.5%. Reduction of energy consumption in the pump was measured by 65% in winter heating and by 47% in summer cooling. 52,000kW of electricity may be saved annually. Around 900days has passed after injection of surfactant, the system works successfully without problems of efficiency and rust.