The present invention relates to an LED illumination apparatus. The apparatus includes a body having a lower portion adapted for coupling to a power socket and an upper portion provided with a power source module accommodating chamber. A heat-dissipating module includes a funnel-shaped hollow case disposed at a top end of the upper portion and filled with a coolant fluid, wherein the hollow case has a small diameter open end adjacent to the body and a large diameter open end remote from the body. A light source module includes amounting substrate disposed at the small diameter open end, an LED mounted on the mounting substrate, and a power source module disposed within the power source module accommodating chamber in a manner electrically connected to and supplying working power to the LED.