A heat pipe (20) includes a pipe (21), a wick (22) formed on an inner wall (23) of the pipe, and a working fluid (not shown) sealed in the pipe and soaked in the wick. The wick is formed by sintering nano-size metal powder disposed inside the pipe. First through holes (25) are defined in the wick in an evaporator section (20a) of the heat pipe. A central one of the first through holes is aligned along an axis 20c of the heat pipe, and other first through holes are parallel to the axis 20c. A second through hole (26) is defined in the wick in a condenser section (20b) of the heat pipe. The second through hole communicates with the first through holes, whereby the working fluid flows through the first and second through holes. These characteristics give the wick low thermal resistance, a high evaporator surface area, and high capillary force.