Abstract: Disclosed is a ladder railing gutter clamp for securing the railing of an upstanding ladder against the outer flange of a roof gutter. The device comprises an angled clamp having a first railing accepting end and a second gutter insertion end. The first end includes a lateral arm secures around the exterior of a ladder railing and an inward tab to prevent lateral motion, while the second end includes a perpendicular turnscrew support arm. A turnscrew threadably mounts through the support arm and is directed toward the clamp first end. The turnscrew support arm is placed within a gutter for advancing the turnscrew towards the interior surface of a gutter outer flange. A pivotable contact pad having high friction surface is connected to the interior end of the turnscrew, which compresses the gutter flange and the ladder railing towards the clamp first end lateral arm.