A heat dissipation device with heat pipes is described. The heat dissipation device has at least one L-shaped heat pipe, a plurality of heat fins, and a heat sink base. One end of the L-shaped heat pipe is coupled to one heat pipe fixing trench of the heat sink base so as to increase a contact area for transmitting heat and therefore improve a heat dissipation efficiency thereof. The heat fins includes at least one upper heat fin and at least one lower heat fin to couple to the L-shaped heat pipe via a round opening and a long opening respectively. The heat dissipation device therefore reduces a volume thereof and save an occupation space in an electrical device.