Till now, water based lubricants, especially aqueous solutions, have not been employed in the elastohydrodynamic lubrication (EHL) due to their poor film forming capability or low wear resistance. In this paper, we proposed a method to develop water based lubricant: employing polyalkylene glycol solution as base stock to improve EHL film forming capability and using organic phosphate ester (DPZ) as anti-wear additive to improve wear resistance property. The lubricating properties of the mixed solutions, including load carrying capability, wear resistance property, friction reduction property, EHL film forming behavior, were investigated. The experimental results indicate that the mixed solution presents excellent lubricating properties, which make it a promising candidate in developing water based lubricants.