A lighting system for a sign consists of a bracket to be attached to the top of a flat sign, the bracket including a surface supporting a battery, a solar battery charging cell and a circuit connecting the battery to an LED lamp directed to illuminate the message on the sign. A second embodiment includes a box-type sign with a housing having a light-transmitting top panel, a message on both side panels, light-transmitting ends, and either one or two mirrors supported on the bottom angled to reflect light against the messages. A support bracket includes straps extending part way across the top panel carrying solar panels, batteries, and a circuit are located under the straps and one or more LED lamps are connected to the circuit and arranged to be powered when the ambient light becomes too low to properly illuminate the message or messages.