A driving support device according to an embodiment includes an estimation unit, a rendering unit, and an erasing unit. The estimation unit estimates a running state of a movable body based on an image taken on the movable body. The rendering unit produces a prediction line that indicates a predicted direction of travel of the movable body based on the running state estimated by the estimation unit, and superimposes and renders the prediction line on the taken image. The erasing unit erases the prediction line rendered by the rendering unit in a case where the estimation unit estimates that the movable body is stopped.