A heat dissipation fin includes multiple unit each having a top, a first side and a second side and multiple bridges each connecting every two adjacent units together and connected to each one of the units at a fold. The bridge has a front side and a rear side and the top of the unit has a first side in parallel with the front side and a second side in parallel with the rear side of the bridge. Each front side has a width smaller than a width of each rear side and each first side has a width smaller than a width of each second side.