A heat-dissipation fan includes a rotary assembly and a plurality of rotary cylinders mounted on an outer surface of the rotary assembly to serve as cylindrical fan blades of the heat-dissipation fan. The rotary assembly includes a plurality of first electrical conducting units and a second electrical conducting unit. The rotary cylinders move along with the rotary assembly when the latter rotates and are correspondingly electrically connected to the first electrical conducting units to be rotatable about their respective centerlines.