A brief introduction on the measurement of key properties of lithium bromide-based working fluid for absorption chiller were presented in order to develop the new working fluid for a specific cycle operation. As possible new working fluids, various systems were considered. LiBr+HO(CH₂)₃OH+H₂O (LiBr/HO(CH₂)₃OH mass ratio=3.5)system was found to be a potential new working fluid for the air-cooled absorption chiller and the result of property measurement were presented. Using the measured properties the DÜhring and enthalpy-concentration diagrams were constructed.