This invention relates to a type of loop heat conducting device, comprising an evaporator and a condenser which are connected together by means of a loop pipe, in order to form a cyclic loop for a liquid working medium, wherein the evaporator has a wick network core, and multiple tunnels are formed on the wick network core, and one end of the tunnels converges at a vapor chamber and is connected to a loop pipe to form a gaseous working medium outlet, and the terminal end of the pipe extends into and comes into contact with the internal part of the wick network core, and a compensation chamber for liquid working medium is formed on the upper section of the wick network core. Consequently, the cyclic loop that separates the gas and liquid enables the optimal heat dissipation capacity, and also has a structure that is simplified, thereby allowing for easy mass production.