The development trend of electronic devices, such as LED chips and CPU chips, gradually become miniaturized and integrated,which account for the over concentration of the high heat flux in the device. The adverse thermal environment can seriously degrade the performance and service lives of electronic devices. The advanced cooling technology is needed to solve the ther-mal problem of the electronic device. Heat pipe technology that utilizes the phase change latent heat of working fluid and transfers the high heat flux fromhot side to cold side is expected to solve the thermal problem of electronic devices. In order to improve and strengthen the heat transport performance of heat pipes, finding out a suitable working fluid is one of the most direct and effective ways