Performance of laminar heat transfer in a channel fitted with two transverse staggered diamond baffle elements is obtained using numerical simulation. The order of enhancement is about 200–680% for using the diamond baffles. However, as expected, the augmentation is associated with enlarged friction loss ranging from 20 to 220 times above the smooth channel. The effect of interaction of the vortices induced by both types of baffles is numerically investigated. The enhancement of heat transfer for the 5° diamond baffle is around 6% higher than that for the flat baffle.