Abstract: A deck light assembly for attachment to a deck railing includes a C-shaped body with a core nesting within a cover and a top plate extending between two legs. The body includes a top plate extending between a first leg and a second leg. An LED light and a battery may each be disposed within the body between the core and the cover. Each of the legs of the core may define a clamping member, with the clamping members in mirror-image pairs across from one-another for securing the deck light assembly upon the deck railing, and each clamping member having a V-shaped cross-section with a top portion extending downwardly and inwardly away from the associated leg to a knuckle, and with a bottom portion extending downwardly from the knuckle and outwardly toward the associated leg. The clamping members may be flexible outwardly for allowing the deck light assembly to be easily removed or repositioned on the deck railing.