Abstract: A loop heat pipe（LHP） was studied with water as the working fluid.The final heat sink was cooled by air.The LHP evaporator consisted of an intercrossed microchannel structure contacted with compressed copper foam piece.Effects of heating power,inclination angle and liquid charge ratio on the thermal performance of LHP were investigated experimentally.The temperature distribution in each component of LHP and the thermal performance data were obtained.The results demonstrate that the optimal thermal performance of the LHP is reached at the liquid charge ratio of 50% and the inclination angle of 270.The maximal temperature at the evaporator surface can be smaller than 85 ℃ at the heating power of 110 W,satisfying the cooling requirement for large power density light emitting diode（LED） and other electronic devices.