Abstract: High power and high brightness light emitting diodes are penetrating into a number of lighting applications due to their excellent color saturation and long life characteristics. In this study, we used Aluminum Oxide (Al2O3) and Aluminum Nitride (AlN) as submount of LED chips and made Chip On Board (COB) type LED module utilizing eutectic bonder. The COB type LED module was made by using metal core printed circuit board and the flipchip on which metal solder was coated. We also fabricated COB type LED modules with epoxy and silicone resins as encapsulant, Al2O3 and AlN as substrates utilizing eutectic and epoxy die bonding methods. In these experiments the effect of AlN substrate was larger than other parameters for high power operation of LED modules.