This paper summarizes the recent developments of lightweight, high performance heat pipes. The applications of lightweight materials can help reduce by up to 80% the weight of conventional copper heat pipes. However the lightweight material often has problems of corrosion. There are still some limitations to the applications of lightweight materials such as magnesium due to its incompatibility with some working fluids. To use water (the most desirable working fluids for normal heat pipes) as a working fluid, aluminum alloys, titanium alloys and magnesium alloys must have additional protection incorporated during the production process in order to avoid non-condensable gas generation.Although many lightweight materials have been investigated, such as aluminum and its alloys, beryllium-based alloys, epoxy-impregnated carbon fiber wound over thin aluminum shells, laminate materials, metal/matrix composites, titanium alloys and magnesium alloy, only one or two materials were applied to the heat pipes (HPs) envelop based on the life tests. Besides using the lightweight materials, minimizing the size of standard heat pipe cooling devices is an alternative way. The main improvement for those heat pipes is focused on optimal wick structures.An alternative direct method to reduce weight is to improve the wick structure of the heat pipes. Using light material (fiber) to make a mixed wick structure, such as mixed mesh and sintering, can help to increase the heat flux in boiling process and also reduce the pressure drop inside the heat pipe which leads to a much lower temperature change in the adiabatic section. By using this method, the performance of the heat pipe is definitely enhanced. However it doesn’t give much of a visible weight reduction. Due to the low permeability and high effective thermal resistance of fiber wicks, these combined with other wicks to make prototypes of lightweight materials.