An LED lamp includes a first heat sink, a lamp base, a plurality of LED modules, an envelope and a second heat sink. The first heat sink includes a cylinder at a centre thereof and a plurality of fins surrounding the cylinder. The lamp base is secured to a bottom portion of the first heat sink. The LED modules are mounted on the fins of the first heat sink. Each of the LED modules includes a printed circuit board and a plurality of LEDs mounted on the printed circuit board. The envelope is mounted between the lamp base and the second heat sink and encloses the first heat sink and the LED modules therein. The second heat sink has a disc-like configuration, with a bottom connecting portion extending through the envelope to connect with a top portion of the first heat sink.