An LED lamp includes a first heat sink, a pair of second heat sinks arranged at two opposite sides of the first heat sink, a plurality of heat pipes connecting the first heat sink to the pair of second heat sinks, and an LED module mounted on the first heat sink. With the help of good heat conducting capability of the heat pipes, heat generated by LEDs of the LED module can be conducted to the first heat sink and the pair of second heat sinks rapidly, which then dissipate the heat to the ambient air. Each second heat sink consists of a plurality of sheets defining a plurality of gaps therebetween; the gaps extend through top and bottom of each second heat sink. Each second heat sink has a lower portion below a bottom surface of the first heat sink.