A security light for a fence includes a light module having an LED unit and a junction box. The junction box contains electrical components for operating the LED unit, and has a rear end with a rear wall and a front end having a front opening that opposes the rear wall. A clamp assembly is coupled with the junction box and opposes the rear end of the junction box to define an opening for a fence post. The front opening of the junction box provides access to the interior of the junction box for conducting electrical wiring operations. A front cover plate is assembled with the junction box for covering the front opening of the junction box. When the junction box is clamped to the fence post, the front cover plate is removable for providing access to the interior of the junction box.